Commit Graph

3439 Commits

Author SHA1 Message Date
Raphael Isemann 8142425727 Revert "[libc++] Workaround timespec_get not always being available in Apple SDKs"
This reverts commit 99f3b231cb. It breaks
libcxx/modules/stds_include.sh.cpp on macOS as the new include to sys/cdefs.h
causes a dependency from __config to the Darwin module (which already has
a dependency on __config). This cyclic dependency breaks compiling the std
module which breaks compiling pretty much every program with ToT libc++ and
enabled modules.

I'll revert for now to get the bots green again. Sorry for the inconvenience.
2020-09-02 09:45:35 +02:00
Eric Fiselier 057028ed39 Revert switch based variant temporarily.
There are currently some failures caused by this change internally. I'm working
to debug them and hopefully these series of patches should be recommitted by
the end of the week.

Thank you to Micheal Park for the contributions, and for allowing the temporary
rollback.

The commits reverted by this change are:

7d15ece79c
e0ec7a0206
02197f7e50
a175a96517
2020-09-01 22:15:33 -04:00
Louis Dionne 99f3b231cb [libc++] Workaround timespec_get not always being available in Apple SDKs
timespec_get is not available in Apple SDKs when (__DARWIN_C_LEVEL >= __DARWIN_C_FULL)
isn't true, which leads to libc++ trying to import ::timespec_get into
namespace std when it's not available. This issue has been reported to
Apple's libc, but we need a workaround in the meantime.

https://llvm.org/PR47208
rdar://68157284
2020-09-01 15:10:50 -04:00
Michael Park 7d15ece79c [libcxx/variant] Implement workaround for GCC bug.
A parameter pack is deemed to be uncaptured, which is bogus... but it seems to
be because it's within an expression that involves `decltype` of an uncaptured
pack or something: https://godbolt.org/z/b8z3sh

Drive-by fix for uglified name.

Differential Revision: https://reviews.llvm.org/D86827
2020-08-30 12:43:14 -04:00
Louis Dionne 316d336dca [libc++] Un-deprecate and un-remove some members of std::allocator
This implements the part of P0619R4 related to the default allocator.
This is incredibly important, since otherwise there is an ABI break
between C++17 and C++20 w.r.t. the default allocator's size_type on
platforms where std::size_t is not the same as std::make_unsigned<std::ptrdiff_t>.
2020-08-28 12:51:51 -04:00
Louis Dionne 21a1a263a6 [libc++][NFC] Define functor's call operator inline
This fixes a mismatched visibility attribute on the call operator in
addition to making the code clearer. Given this is a simple lambda
in essence, the intent has always been to give it inline visibility.
2020-08-27 14:20:34 -04:00
Mikhail Maltsev a19fd1aab5 Revert "[libcxx] Fix compile for BUILD_EXTERNAL_THREAD_LIBRARY"
This reverts commit 3b71f91558.

The commit is breaking some build bots.
2020-08-27 16:48:10 +01:00
David Nicuesa 3b71f91558 [libcxx] Fix compile for BUILD_EXTERNAL_THREAD_LIBRARY
Fix compilation with -DLIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY when using clang. Now linking target  'cxx_external_threads' with 'cxx-headers'. Fix mismatching visibility for `libcpp_timed_backoff_policy` function in file <__threading_support>.

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D86598
2020-08-27 16:24:19 +01:00
Michael Park e0ec7a0206
[libcxx/variant] Correctly propagate return type of the visitor.
The tests for it were missing so I've added them.

Reviewed By: #libc, EricWF

Differential Revision: https://reviews.llvm.org/D86006
2020-08-17 10:53:59 -07:00
Michael Park 02197f7e50
[libcxx/variant] Avoided variable name shadowing. 2020-08-14 16:30:27 -07:00
Michael Park a175a96517
[libcxx/variant] Introduce `switch`-based mechanism for `std::visit`.
This patch introduces mechanism for `std::visit` backed by `switch`.
The `switch` is structured such that it's a flattened manual vtable (an n-ary array).
The `switch` mechanism is enabled if `(1 * ... * vs.size()) < 1024`.

The following are performance numbers from the benchmarks added in D85419, tested on my 2017 Macbook Pro.

```
$ ./projects/libcxx/benchmarks/variant_visit_1.libcxx.out
2020-08-09 23:55:14
Running ./projects/libcxx/benchmarks/variant_visit_1.libcxx.out
Run on (8 X 3100 MHz CPU s)
CPU Caches:
  L1 Data 32K (x4)
  L1 Instruction 32K (x4)
  L2 Unified 262K (x4)
  L3 Unified 8388K (x1)
Load Average: 2.03, 2.36, 2.43
------------------------------------------------------------
Benchmark                 Time             CPU   Iterations
------------------------------------------------------------
BM_Visit<1, 1>        0.260 ns        0.260 ns   1000000000
BM_Visit<1, 2>         1.56 ns         1.56 ns    435925220
BM_Visit<1, 3>         1.55 ns         1.55 ns    444416228
BM_Visit<1, 4>         1.57 ns         1.57 ns    427951336
BM_Visit<1, 5>         1.57 ns         1.56 ns    444766371
BM_Visit<1, 6>         1.70 ns         1.68 ns    446639358
BM_Visit<1, 7>         1.64 ns         1.64 ns    400441630
BM_Visit<1, 8>         1.56 ns         1.56 ns    430729471
BM_Visit<1, 9>         1.58 ns         1.58 ns    449894596
BM_Visit<1, 10>        1.54 ns         1.54 ns    449660506
BM_Visit<1, 20>        1.56 ns         1.56 ns    450813074
BM_Visit<1, 30>        1.59 ns         1.59 ns    440032940
BM_Visit<1, 40>        1.59 ns         1.59 ns    443731656
BM_Visit<1, 50>        1.56 ns         1.56 ns    444709859
BM_Visit<1, 60>        1.59 ns         1.58 ns    439527320
BM_Visit<1, 70>        1.57 ns         1.57 ns    438450890
BM_Visit<1, 80>        1.58 ns         1.58 ns    443001525
BM_Visit<1, 90>        1.63 ns         1.62 ns    448456349
BM_Visit<1, 100>       1.57 ns         1.57 ns    445740630

$ ./projects/libcxx/benchmarks/variant_visit_2.libcxx.out
2020-08-09 23:59:35
Running ./projects/libcxx/benchmarks/variant_visit_2.libcxx.out
Run on (8 X 3100 MHz CPU s)
CPU Caches:
  L1 Data 32K (x4)
  L1 Instruction 32K (x4)
  L2 Unified 262K (x4)
  L3 Unified 8388K (x1)
Load Average: 1.40, 1.94, 2.22
-----------------------------------------------------------
Benchmark                Time             CPU   Iterations
-----------------------------------------------------------
BM_Visit<2, 1>       0.261 ns        0.260 ns   1000000000
BM_Visit<2, 2>        1.55 ns         1.54 ns    432844219
BM_Visit<2, 3>        1.30 ns         1.30 ns    532529974
BM_Visit<2, 4>        1.54 ns         1.54 ns    446055910
BM_Visit<2, 5>        1.31 ns         1.31 ns    531099680
BM_Visit<2, 6>        1.56 ns         1.56 ns    443203475
BM_Visit<2, 7>        1.29 ns         1.29 ns    526478087
BM_Visit<2, 8>        1.56 ns         1.56 ns    439000834
BM_Visit<2, 9>        1.30 ns         1.30 ns    528756817
BM_Visit<2, 10>       1.56 ns         1.55 ns    442923039
BM_Visit<2, 20>       1.35 ns         1.35 ns    517021072
BM_Visit<2, 30>       1.60 ns         1.59 ns    419724661
BM_Visit<2, 40>       1.45 ns         1.44 ns    472137163
BM_Visit<2, 50>       1.65 ns         1.65 ns    421389743

$ ./projects/libcxx/benchmarks/variant_visit_3.libcxx.out
2020-08-10 00:01:32
Running ./projects/libcxx/benchmarks/variant_visit_3.libcxx.out
Run on (8 X 3100 MHz CPU s)
CPU Caches:
  L1 Data 32K (x4)
  L1 Instruction 32K (x4)
  L2 Unified 262K (x4)
  L3 Unified 8388K (x1)
Load Average: 2.20, 2.01, 2.21
-----------------------------------------------------------
Benchmark                Time             CPU   Iterations
-----------------------------------------------------------
BM_Visit<3, 1>       0.272 ns        0.271 ns   1000000000
BM_Visit<3, 2>        1.87 ns         1.86 ns    361858090
BM_Visit<3, 3>        1.77 ns         1.77 ns    391192579
BM_Visit<3, 4>        1.84 ns         1.84 ns    374694223
BM_Visit<3, 5>        1.75 ns         1.75 ns    408270392
BM_Visit<3, 6>        1.88 ns         1.88 ns    378759185
BM_Visit<3, 7>        1.79 ns         1.79 ns    395498102
BM_Visit<3, 8>        1.85 ns         1.85 ns    371660366
BM_Visit<3, 9>        1.80 ns         1.80 ns    386872851
BM_Visit<3, 10>       1.84 ns         1.84 ns    362367606
BM_Visit<3, 15>       1.77 ns         1.77 ns    392060220
BM_Visit<3, 20>       1.85 ns         1.85 ns    379157188
```

```
$ ./projects/libcxx/benchmarks/variant_visit_1.libcxx.out
2020-08-10 00:05:57
Running ./projects/libcxx/benchmarks/variant_visit_1.libcxx.out
Run on (8 X 3100 MHz CPU s)
CPU Caches:
  L1 Data 32K (x4)
  L1 Instruction 32K (x4)
  L2 Unified 262K (x4)
  L3 Unified 8388K (x1)
Load Average: 2.27, 2.36, 2.34
------------------------------------------------------------
Benchmark                 Time             CPU   Iterations
------------------------------------------------------------
BM_Visit<1, 1>        0.271 ns        0.271 ns   1000000000
BM_Visit<1, 2>        0.269 ns        0.269 ns   1000000000
BM_Visit<1, 3>        0.271 ns        0.271 ns   1000000000
BM_Visit<1, 4>        0.270 ns        0.270 ns   1000000000
BM_Visit<1, 5>        0.269 ns        0.269 ns   1000000000
BM_Visit<1, 6>        0.270 ns        0.269 ns   1000000000
BM_Visit<1, 7>        0.265 ns        0.265 ns   1000000000
BM_Visit<1, 8>        0.269 ns        0.269 ns   1000000000
BM_Visit<1, 9>        0.268 ns        0.268 ns   1000000000
BM_Visit<1, 10>       0.269 ns        0.269 ns   1000000000
BM_Visit<1, 20>       0.267 ns        0.267 ns   1000000000
BM_Visit<1, 30>       0.272 ns        0.272 ns   1000000000
BM_Visit<1, 40>       0.268 ns        0.268 ns   1000000000
BM_Visit<1, 50>       0.268 ns        0.268 ns   1000000000
BM_Visit<1, 60>       0.268 ns        0.268 ns   1000000000
BM_Visit<1, 70>       0.269 ns        0.269 ns   1000000000
BM_Visit<1, 80>       0.266 ns        0.266 ns   1000000000
BM_Visit<1, 90>       0.268 ns        0.268 ns   1000000000
BM_Visit<1, 100>      0.267 ns        0.267 ns   1000000000

$ ./projects/libcxx/benchmarks/variant_visit_2.libcxx.out
2020-08-12 04:09:59
Running ./projects/libcxx/benchmarks/variant_visit_2.libcxx.out
Run on (8 X 3100 MHz CPU s)
CPU Caches:
  L1 Data 32K (x4)
  L1 Instruction 32K (x4)
  L2 Unified 262K (x4)
  L3 Unified 8388K (x1)
Load Average: 2.17, 4.20, 4.78
-----------------------------------------------------------
Benchmark                Time             CPU   Iterations
-----------------------------------------------------------
BM_Visit<2, 1>       0.302 ns        0.301 ns   1000000000
BM_Visit<2, 2>       0.297 ns        0.295 ns   1000000000
BM_Visit<2, 3>       0.353 ns        0.351 ns   1000000000
BM_Visit<2, 4>       0.276 ns        0.276 ns   1000000000
BM_Visit<2, 5>       0.285 ns        0.283 ns   1000000000
BM_Visit<2, 6>       0.290 ns        0.287 ns   1000000000
BM_Visit<2, 7>       0.282 ns        0.280 ns   1000000000
BM_Visit<2, 8>       0.290 ns        0.287 ns   1000000000
BM_Visit<2, 9>       0.291 ns        0.285 ns   1000000000
BM_Visit<2, 10>      0.293 ns        0.287 ns   1000000000
BM_Visit<2, 20>       1.70 ns         1.68 ns    391400375
BM_Visit<2, 30>       1.64 ns         1.63 ns    418925874
BM_Visit<2, 40>       1.63 ns         1.62 ns    423623677
BM_Visit<2, 50>       1.68 ns         1.67 ns    411687212

$ ./projects/libcxx/benchmarks/variant_visit_3.libcxx.out
2020-08-12 04:10:43
Running ./projects/libcxx/benchmarks/variant_visit_3.libcxx.out
Run on (8 X 3100 MHz CPU s)
CPU Caches:
  L1 Data 32K (x4)
  L1 Instruction 32K (x4)
  L2 Unified 262K (x4)
  L3 Unified 8388K (x1)
Load Average: 1.57, 3.76, 4.59
-----------------------------------------------------------
Benchmark                Time             CPU   Iterations
-----------------------------------------------------------
BM_Visit<3, 1>       0.271 ns        0.270 ns   1000000000
BM_Visit<3, 2>       0.344 ns        0.334 ns   1000000000
BM_Visit<3, 3>       0.347 ns        0.336 ns   1000000000
BM_Visit<3, 4>       0.300 ns        0.296 ns   1000000000
BM_Visit<3, 5>       0.290 ns        0.286 ns   1000000000
BM_Visit<3, 6>       0.272 ns        0.271 ns   1000000000
BM_Visit<3, 7>        1.72 ns         1.71 ns    415765841
BM_Visit<3, 8>        1.73 ns         1.72 ns    408909555
BM_Visit<3, 9>        2.16 ns         2.04 ns    380898485
BM_Visit<3, 10>       2.45 ns         2.40 ns    295714256
BM_Visit<3, 15>       1.92 ns         1.85 ns    375990332
BM_Visit<3, 20>       1.66 ns         1.65 ns    414456233
```

Differential Revision: https://reviews.llvm.org/D85420
2020-08-14 12:54:58 -07:00
Louis Dionne 8d4860aa9e [libc++] Remove workarounds for missing rvalue references
We don't support GCC in C++03 mode, and Clang provides rvalue references
even in C++03 mode. So there's effectively no supported compiler that
doesn't support rvalue references.

Differential Revision: https://reviews.llvm.org/D84943
2020-08-12 12:02:28 -04:00
Evgenii Stepanov 189ba3db86 Fix CFI issues in <future>
This change fixes errors reported by Control Flow Integrity (CFI) checking when using `std::packaged_task`.  The errors mostly stem from casting the underlying storage (`__buf_`) to `__base*`, even if it is uninitialized.  The solution is to wrap `__base*` access to `__buf_` behind a getter marked with _LIBCPP_NO_CFI.

Differential Revision: https://reviews.llvm.org/D82627
2020-08-06 12:05:22 -07:00
Louis Dionne 19bc9ea480 [libc++] Avoid including <Block.h> from <functional>
Block.h is a pretty common name, which can lead to nasty collisions with
user provided headers. Since we're only getting a few simple declarations
from the header, it's better to declare them manually than to include the
header.

rdar://66384326

Differential Revision: https://reviews.llvm.org/D85035
2020-07-31 14:22:28 -04:00
Louis Dionne 67dfba9629 [libc++] Provide std::aligned_alloc and std::timespec_get on Apple platforms
rdar://66113878
2020-07-28 15:13:05 -04:00
Louis Dionne 1bd7c02233 [libc++] Clean up tests for "optional" C11 features
First, add a TEST_HAS_QUICK_EXIT macro to mirror other C11 features like
TEST_HAS_ALIGNED_ALLOC, and update the tests for that.

Second, get rid of TEST_HAS_C11_FEATURES and _LIBCPP_HAS_C11_FEATURES,
which were only used to ensure that feature macros don't get out of
sync between <__config> and "test_macros.h". This is not necessary
anymore, since we have tests for each individual macro now.
2020-07-28 15:13:05 -04:00
Louis Dionne 9798b2311f [libc++] Make sure we only consider _GNUC_VER_NEW when the compiler is GCC
When the compiler is Clang, _GNUC_VER_NEW is 0, which messes up the logic.
2020-07-22 16:08:19 -04:00
Louis Dionne e9748a7255 [libc++] Workaround broken support for C++17 in GCC 5 2020-07-22 15:38:58 -04:00
Vy Nguyen 76887bc4c1 Reland [libcxx]Put clang::trivial_abi on smart pointers
Reviewed By: ldionne,EricWF

    Tags: #libcxx

    Differential Revision: https://reviews.llvm.org/D82490
2020-07-20 11:54:34 -04:00
Hans Wennborg 7ab7b979d2 Bump the trunk major version to 12
and clear the release notes.
2020-07-15 12:05:05 +02:00
Louis Dionne eaca1e4e54 [libc++] Automatically detect whether RTTI is enabled
Instead of detecting it automatically but also allowing for the setting
to be specified explicitly, always detect whether exceptions are enabled
based on whether -fno-rtti (or equivalent) is used. It's less confusing
to have a single way of tweaking that knob.

This change follows the lead of 71d88cebfb.
2020-07-14 16:51:37 -04:00
Louis Dionne efa40eb194 [libc++] Use a proper CMake target to represent libc++ headers
Instead of having complex logic around how to include the libc++ headers
and __config_site, handle that by defining cxx-headers as an INTERFACE
library and linking against it. After this patch, linking against cxx-headers
is sufficient to get the right __config_site include and include paths
for libc++.

Differential Revision: https://reviews.llvm.org/D82702
2020-07-14 09:52:58 -04:00
Louis Dionne 2d3b8cc83f [libc++] Implement P0551
Make sure we satisfy the requirements added by P0551, and add tests to
enforce that.
2020-07-13 13:42:26 -04:00
Michael Park 6ab3208d77
Remove the unnecessary `is_nothrow_swappable` condition in `swap`.
Thanks to @lewissbaker who pointed out the unnecessary condition in
https://reviews.llvm.org/D81954#inline-756872. Since this codepath does not
make use of `swap` anyway (that codepath is a different branch), we can safely
remove this condition and produce better codegen when all types are nothrow
movable but are potentially-throwing swappable.

See codegen in https://gcc.godbolt.org/z/uDFZjz

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D83274
2020-07-08 10:46:38 -07:00
Stephan Herhut 3341d470fc Revert "Revert "Revert "[libcxx] Put clang::trivial_abi on std::unique_ptr, std::shared_ptr, and std::weak_ptr"""
This reverts commit f706b01a00.
2020-07-06 12:18:17 +02:00
Vy Nguyen f706b01a00 Revert "Revert "[libcxx] Put clang::trivial_abi on std::unique_ptr, std::shared_ptr, and std::weak_ptr""
This reverts commit dc13ac0280.

Rolling forward + fix typos and unused variables in tests

    Differential Revision: https://reviews.llvm.org/D82490
2020-07-05 13:44:42 -04:00
Vy Nguyen dc13ac0280 Revert "[libcxx] Put clang::trivial_abi on std::unique_ptr, std::shared_ptr, and std::weak_ptr"
This reverts commit 5cde3c9633.

The tests were reported failing on clang10
2020-07-04 11:29:08 -04:00
Vy Nguyen 5cde3c9633 [libcxx] Put clang::trivial_abi on std::unique_ptr, std::shared_ptr, and std::weak_ptr
Reviewers: jyknight, EricWF, #libc!

Subscribers: arphaman, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D82490
2020-07-03 17:23:13 -04:00
Louis Dionne 71d88cebfb [libc++/libc++abi] Automatically detect whether exceptions are enabled
Instead of detecting it automatically (in libc++) and relying on
_LIBCXXABI_NO_EXCEPTIONS being set explicitly (in libc++abi), always
detect whether exceptions are enabled automatically.

This commit also removes support for specifying -D_LIBCPP_NO_EXCEPTIONS
and -D_LIBCXXABI_NO_EXCEPTIONS explicitly -- those should just be inferred
from using -fno-exceptions (or an equivalent flag).

Allowing both -D_FOO_NO_EXCEPTIONS to be provided explicitly and trying
to detect it automatically is just confusing, especially since we did
specify it explicitly when building libc++abi. We should have only one
way to detect whether exceptions are enabled, but it should be robust.
2020-07-03 14:58:09 -04:00
Martijn Vels 2bad222680 Add optimization to basic_string::assign for compile-time known constant values.
Summary:
This change optimizes the assign() methods for string where either the contents or lengths are compile time known constants. For small strings (< min_cap) we can execute the assignment entirely inline. For strings up to 128 bytes we allow the compiler to efficiently inline the copy operation after we call the offline __resize<>() method. Short / long branches are taken at the call site for better branch prediction and allowing FDO optimizations.

Benchmarks (unstable / google perflab):
```
name                                                old time/op             new time/op             delta
BM_StringAssignAsciiz_Empty_Opaque                  5.69ns ± 7%             5.97ns ± 7%     ~             (p=0.056 n=5+5)
BM_StringAssignAsciiz_Empty_Transparent             5.39ns ± 7%             0.79ns ± 8%  -85.36%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Small_Opaque                  11.2ns ± 5%             11.0ns ± 6%     ~             (p=0.548 n=5+5)
BM_StringAssignAsciiz_Small_Transparent             10.1ns ± 7%              1.0ns ± 8%  -89.76%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Large_Opaque                  23.5ns ± 7%             23.8ns ± 7%     ~             (p=0.841 n=5+5)
BM_StringAssignAsciiz_Large_Transparent             21.4ns ± 7%             12.7ns ± 7%  -40.83%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Huge_Opaque                    336ns ± 4%              327ns ± 7%     ~             (p=0.421 n=5+5)
BM_StringAssignAsciiz_Huge_Transparent               331ns ± 5%              324ns ± 7%     ~             (p=0.548 n=5+5)
BM_StringAssignAsciizMix_Opaque                     13.6ns ±10%             13.7ns ± 9%     ~             (p=0.690 n=5+5)
BM_StringAssignAsciizMix_Transparent                12.9ns ± 8%              3.6ns ± 8%  -71.82%          (p=0.008 n=5+5)
```

Reviewers: EricWF, #libc!

Subscribers: jfb, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D82221
2020-06-29 14:34:34 -04:00
Louis Dionne 8bc62db272 [libc++] Remove support for building through llvm-config
We've decided to move away from that by requiring that libc++ is built
as part of the monorepo a while ago. This commit removes code pertaining
to that unsupported use case and produces a clear error when the user
violates that.

In fact, building outside of the monorepo will still work as long as
LLVM_PATH is pointing to the root of the LLVM project, although that
is not officially supported.
2020-06-26 15:13:04 -04:00
Louis Dionne 05c552ad05 [libc++] Fix the runtimes build after making __config_site mandatory
The runtimes build includes libcxx/include/CMakeLists.txt directly instead
of going through the top-level CMake file. This not-very-hygienic inclusion
caused some variables like LIBCXX_BINARY_DIR not to be defined properly,
and the config_site generation logic to fail after landing 53623d4aa7.

This patch works around this issue by defining the missing variables.
However, the proper fix for this would be for the runtimes build to
always go through libc++'s top-level CMakeLists.txt. Doing otherwise
is unsupported.
2020-06-26 01:26:34 -04:00
Louis Dionne 53623d4aa7 [libc++] Always generate a __config_site header
Before this patch, the __config_site header was only generated when at
least one __config_site macro needed to be defined. This lead to two
different code paths in how libc++ is configured, depending on whether
a __config_site header was generated or not. After this patch, the
__config_site is always generated, but it can be empty in case there
are no macros to define in it.

More context on why this change is important
--------------------------------------------
In addition to being confusing, this double-code-path situation lead to
broken code being checked in undetected in 2405bd6898, which introduced
the LIBCXX_HAS_MERGED_TYPEINFO_NAMES_DEFAULT CMake setting. Specifically,
the _LIBCPP_HAS_MERGED_TYPEINFO_NAMES_DEFAULT <__config_site> macro was
supposed NOT to be defined unless LIBCXX_HAS_MERGED_TYPEINFO_NAMES_DEFAULT
was specified explicitly on the CMake command line. Instead, what happened
is that it was defined to 0 if it wasn't specified explicitly and a
<__config_site> header was generated. And defining that macro to 0 had
the important effect of using the non-unique RTTI comparison implementation,
which changes the ABI.

This change in behavior wasn't noticed because the <__config_site> header
is not generated by default. However, the Apple configuration does cause
a <__config_site> header to be generated, which lead to the wrong RTTI
implementation being used, and to https://llvm.org/PR45549. We came close
to an ABI break in the dylib, but were saved due to a downstream-only
change that overrode the decision of the <__config_site> for the purpose
of RTTI comparisons in libc++abi. This is an incredible luck that we should
not rely on ever again.

While the problem itself was fixed with 2464d8135e by setting
LIBCXX_HAS_MERGED_TYPEINFO_NAMES_DEFAULT explicitly in the Apple
CMake cache and then in d0fcdcd28f by making the setting less
brittle, the point still is that we should have had a single code
path from the beginning. Unlike most normal libraries, the macros
that configure libc++ are really complex, there's a lot of them and
they control important properties of the C++ runtime. There must be
a single code path for that, and it must be simple and robust.

Differential Revision: https://reviews.llvm.org/D80927
2020-06-26 00:47:48 -04:00
Louis Dionne 8808574e74 [libc++] Add missing <stddef.h> include to <wchar.h>
It is needed because <wchar.h> uses size_t.
2020-06-25 19:27:32 -04:00
Louis Dionne 06be4bb5e6 [libc++] Remove deprecated _LIBCPP_ALTERNATE_STRING_LAYOUT macro
We use the _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT macro for that now instead.
I did leave a check behind to make sure that nobody was still using the old
macro name. I'll remove it a couple of months down the road.
2020-06-25 16:33:30 -04:00
Arthur O'Dwyer d8e3e55857 [libc++] Fix some typos in the comment header for <regex>
No functional change because all the changed "code" is actually inside
comments.

Differential Revision: https://reviews.llvm.org/D82589
2020-06-25 15:34:51 -04:00
Raul Tambre 98eb1457ff [libc++] Require concepts support for <numbers>
Similar to <concepts>, we need to protect the header and test against
inclusion and being run if concepts aren't supported by the compiler.

Differential Revision: https://reviews.llvm.org/D82171
2020-06-19 10:49:44 -04:00
Raul Tambre 4f6c4b473c [libc++] Implement <numbers>
Summary: Constants have 33 significant decimal digits for IEEE 754 128-bit floating-point numbers.

Reviewers: ldionne, #libc, EricWF, zoecarver, curdeius

Reviewed By: ldionne, #libc, curdeius

Differential Revision: https://reviews.llvm.org/D77505
2020-06-19 14:25:02 +05:30
Martijn Vels d96aac4354 Optimize 'construct at end' loops in vector
Summary:
This change adds local 'end' and 'pos' variables for the main loop inmstead of using the ConstructTransaction variables directly.

We observed that not all vector initialization and resize operations got properly vectorized, i.e., (partially) unrolled into XMM stores for floats.

For example, `vector<int32_t> v(n, 1)` gets vectorized, but `vector<float> v(n, 1)`. It looks like the compiler assumes the state is leaked / aliased in the latter case (unclear how/why for float, but not for int32), and because of this fails to see vectorization optimization?

See https://gcc.godbolt.org/z/UWhiie

By using a local `__new_end_` (fixed), and local `__pos` (copied into __tx.__pos_ per iteration), we offer the compiler a clean loop for unrolling.

A demonstration can be seen in the isolated logic in https://gcc.godbolt.org/z/KoCNWv

The com

Reviewers: EricWF, #libc!

Subscribers: libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D82111
2020-06-18 13:51:12 -04:00
Christopher Di Bella ec789a41e2 [libc++] Add equality for spaceship types for themselves
- Adds operator==(partial_ordering, partial_ordering)
- Adds operator==(weak_ordering, weak_ordering)
- Adds operator==(strong_ordering, strong_ordering)

Differential Revision: https://reviews.llvm.org/D81823
2020-06-18 10:22:50 -04:00
Michael Park 8fbd6d99a0
[libcxx/variant] Fix build error for when exceptions disabled.
Reviewers: #libc!

Subscribers: libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D81973
2020-06-18 07:21:42 -07:00
Michael Park ada2a8ea4a
Remove the try/catch codepath if `swap` is `noexcept`.
Summary:
In the case where `swap` is `noexcept`, we should avoid the extension to provide strong-exception guarantee.

Fixes https://bugs.llvm.org/show_bug.cgi?id=46342

Reviewers: #libc, ldionne

Reviewed By: #libc, ldionne

Subscribers: dexonsmith, mclow.lists, miscco, ldionne, zoecarver, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D81954
2020-06-16 14:51:22 -07:00
Louis Dionne 12b01ab7fa [libc++] Don't trigger unsigned conversion warnings in std::advance
The Standard documents the signature of std::advance as

    template <class Iter, class Distance>
    constexpr void advance(Iter& i, Distance n);

Furthermore, it does not appear to put any restriction on what the type
of Distance should be. While it is understood that it should usually
be std::iterator_traits::difference_type, I couldn't find any wording
that mandates that. Similarly, I couldn't find wording that forces the
distance to be a signed type.

This patch changes std::advance to accept any type in the second argument,
which appears to be what the Standard mandates. We then coerce it to the
iterator's difference type, but that's an implementation detail.

Differential Revision: https://reviews.llvm.org/D81425
2020-06-16 13:47:47 -04:00
Joel E. Denny d9a42ec98a [libc++] Work around gcc/Power9 bug in `include/thread`
This fixes PR39696, which breaks the libcxx build with gcc (I tested
7.5.0) on Power9.  This fix was suggested at

https://bugs.llvm.org/show_bug.cgi?id=39696#c38

but never applied.  It just reverts 0583d9ea8d, which reverses
components of the original fix in 3bf63cf3b3, which is correct.

Fixes https://llvm.org/PR39696

Reviewed By: ldionne

Differential Revision: https://reviews.llvm.org/D81438
2020-06-10 12:40:43 -04:00
Louis Dionne 7fb40e1569 [libc++] Fix too stringent availability markup for bad_optional_access
The availability markup for bad_optional_access marked it as being added
in MacOS 10.14 and aligned releases, however it appears to have been added
in Mac OS 10.13 and aligned releases.
2020-06-09 14:39:51 -04:00
Louis Dionne 1f48f8f6e2 [libc++] Avoid UB in year_month_day_last::day() for incorrect months
This effectively implements the resolution of LWG3231, which mandates
that calling year_month_day_last::day() on an invalid year_month_day_last
is unspecified behavior. Before this change, it was undefined behavior.

Differential Revision: https://reviews.llvm.org/D81477
2020-06-09 13:43:13 -04:00
Louis Dionne cb347a1106 [libc++] Remove assertion in year_month_day_last::day()
This reverts commit 0c148430cf, which added an assertion in day().
The Standard doesn't allow day() to crash -- instead it says that the
result is unspecified.

Differential Revision: https://reviews.llvm.org/D70346
2020-06-09 10:46:13 -04:00
zoecarver b1b64dbef1 [NFC] [libcxx] Remove shared_ptr's no-rvalue unique_ptr converting constructor.
All compilers supported by libc++ have rvalues in C++03 mode so, there is no need for this non-rvalue overload.

Differential Revision: https://reviews.llvm.org/D80881
2020-06-08 09:49:21 -07:00
Louis Dionne 62cfa3a0b5 [libc++] Support move construction and assignment in <thread> in C++03
Libc++ provides support for <thread> in C++03 as an extension. Furthermore,
it does not support any compiler that doesn't have rvalue references. It
is hence possible to provide the move constructor and move assignment
operator in C++03.
2020-06-03 12:16:27 -04:00
Olivier Giroux 06aaf0b343 Updated synopsis of <atomic> to match what is implemented 2020-06-01 14:30:13 -07:00
Louis Dionne 23776a178f [libc++] Add assertions on OOB accesses in std::array when the debug mode is enabled
Like we do for empty std::array, make sure we have assertions in place
for obvious out-of-bounds issues in std::array when the debug mode is
enabled (which isn't by default).
2020-06-01 16:37:39 -04:00
Louis Dionne 66a14d151e [libc++] NFC: Minor refactoring in std::array 2020-06-01 16:28:44 -04:00
Louis Dionne 7265ff928a [libc++] Fix issues with the triviality of std::array
The Standard is currently unimplementable. We have to pick between:

1. Not implementing constexpr support properly in std::array<T, 0>
2. Making std::array<T, 0> non-trivial even when T is trivial
3. Returning nullptr from std::array<T, 0>::begin()

Libc++ initially picked (1). In 77b9abfc8e, we started implementing constexpr properly, but lost the guarantee of triviality. Since it seems like both (1) and (2) are really important, it seems like (3) is the only viable option for libc++, after all. This is also what other implementations are doing.

This patch moves libc++ from (1) to (3).

It also:
- Improves the test coverage for the various ways of initializing std::array
- Adds tests for the triviality of std::array
- Adds tests for the aggregate-ness of std::array

Reviewed By: #libc, miscco, EricWF, zoecarver

Differential Revision: https://reviews.llvm.org/D80821
2020-05-29 16:32:55 -07:00
Louis Dionne d0fcdcd28f [libc++] Fix the LIBCXX_HAS_MERGED_TYPEINFO_NAMES_DEFAULT setting
When the __config_site header is generated, but LIBCXX_HAS_MERGED_TYPEINFO_NAMES_DEFAULT
wasn't specified, _LIBCPP_HAS_MERGED_TYPEINFO_NAMES_DEFAULT would be defined
to 0, which was the NonUnique RTTI comparison implementation. The intent
was to use the Unique RTTI comparison implementation in that case, which
caused https://llvm.org/PR45549.

Instead, use a proper "switch" to select the RTTI comparison implementation.
Note that 0 can't be used as a value, because that is treated the same
by CMake as a variable that is just not defined.

Differential Revision: https://reviews.llvm.org/D80037
2020-05-29 06:14:30 -04:00
Louis Dionne ebddf90a4e [libc++] NFC: Remove outdated numbering in <bit> synopsis 2020-05-28 14:31:21 -04:00
Louis Dionne 77b9abfc8e [libc++] Complete overhaul of constexpr support in std::array
This commit adds missing support for constexpr in std::array under all
standard modes up to and including C++20. It also transforms the <array>
tests to check for constexpr-friendliness under the right standard modes.

Fixes https://llvm.org/PR40124
Fixes rdar://57522096
Supersedes https://reviews.llvm.org/D60666

Differential Revision: https://reviews.llvm.org/D80452
2020-05-28 12:31:06 -04:00
Marek Kurdej d1dbda10ce [libc++] [LWG3201] Update status page: lerp should be marked noexcept.
Summary: Update status page and test synopsis. Add synopsis in <cmath>.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D80456
2020-05-25 22:28:21 +02:00
zoecarver 6e48a6e407 [libcxx] Fix deprecation warning by suppressing deprecated around
__test_has_construct.

In C++17 some tests started failing after a521532aa1. This fixes those errors by suppressing the deprecation warning when calling `construct` in `__test_has_construct`. This is the same solution as `__has_destroy_test` already uses.

Reviewers: ldionne, #libc!

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80481
2020-05-23 14:33:10 -07:00
zoecarver a521532aa1 [NFC] Remove non-variadic overloads of allocator_traits::construct.
Summary:
Libcxx only supports compilers with variadics. We can safely remove all "fake" variadic overloads of allocator_traits::construct.

This also provides the correct behavior if anything other than exactly one argument is supplied to allocator_traits::construct in C++03 mode.

Reviewers: ldionne, #libc!

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80067
2020-05-23 14:03:47 -07:00
Marek Kurdej 174322c273 [libc++] Mark __cpp_lib_hardware_interference_size as unimplemented. This fxes bug PR41423.
Summary:
As described in the bug report:
The commit a8b9f59e8caf378d56e8bfcecdb22184cdabf42d "Implement feature test macros using a script" added test features macros for libc++. Among others, it added `__cpp_lib_hardware_interference_size`. However, there is nothing like std::hardware_constructive_interference_size nor std::hardware_destructive_interference_size, that should be in header <new>.

* https://bugs.llvm.org/show_bug.cgi?id=41423

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D80431
2020-05-23 14:33:50 +02:00
Louis Dionne 485b9083fe [libc++] Mark __u64toa and __u32toa as noexcept
The two functions don't throw, and the generated code is better when
we explicitly tell the compiler that the functions are noexcept. This
isn't an ABI break because the signatures of the functions stay the
same with or without noexcept.

Fixes https://llvm.org/PR46016

Differential Revision: https://reviews.llvm.org/D80379
2020-05-22 16:11:44 -04:00
Louis Dionne 0161874c04 [libc++] NFC: Inline array<T,N>::at methods inside the class
All other methods are defined in the class, so this increases consistency.
2020-05-22 09:24:07 -04:00
Marek Kurdej 0c148430cf Reland [libc++] [LWG3321] Mark "year_month_day_last::day() specification does not cover !ok() values" issue as "Nothing to do", but add assertion.
Summary:
This LWG issue states that the result of `year_month_day_last::day()` is implementation defined if `ok()` is `false`.
However, from user perspective, calling `day()` in this situation will lead to a (possibly difficult to find) crash.
Hence, I have added an assertion to warn user at least when assertions are enabled.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D70346
2020-05-21 21:55:38 +02:00
David Nicuesa 3411a1a920 Fix compile for -DLIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY
Summary: Compilation with  -DLIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY was failing due to missing declarations of functions used in libcxx/include/atomic. The lines this commit affects are the places where those functions are defined, now moved to be always defined.

Reviewers: #libc, ldionne

Reviewed By: #libc, ldionne

Subscribers: miyuki, dexonsmith, ldionne, jfb, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80372
2020-05-21 13:48:59 +01:00
Jan Wilken Dörrie 416b1560c5 [libcxx] Remove swap for std::span
This change removes both the member function swap and the free function
overload of swap for std::span. While swap is a member and overloaded
for every other container in the standard library [1], it is neither a
member function nor a free function overload for std::span [2].
Thus the corresponding implementation should be removed.

[1] https://eel.is/c++draft/libraryindex#:swap
[2] https://eel.is/c++draft/span.overview

Differential Revision: https://reviews.llvm.org/D69827
2020-05-20 14:34:21 -04:00
zoecarver ca5bff18fc [NFC] Remove non-rvlaue non-variadic allocator::construct overloads.
Summary: All supported compilers have rvalues and variadics so we can safely remove the overloads of allocator::construct which are only enabled on compilers without rvalues and variadics.

Reviewers: ldionne, #libc!

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80068
2020-05-19 17:25:00 -07:00
zoecarver b8998ab9c2 [NFC] Remove non-rvlaue non-variadic allocator::construct overloads.
Summary: All supported compilers have rvalues and variadics so we can safely remove the overloads of allocator::construct which are only enabled on compilers without rvalues and variadics.

Reviewers: ldionne, #libc!

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80068
2020-05-19 17:21:35 -07:00
zoecarver 21d4050e2c Mark shared_ptr::__create_with_control_block as noexcept.
Summary: The default constructor for shared_ptr and shared_ptr::__enable_weak_this are both noexcept so, shared_ptr::__create_with_control_block can also be marked noexcept.

Reviewers: ldionne, #libc!

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80070
2020-05-19 17:17:16 -07:00
zoecarver c98648a175 [NFC] Add _EnableIfLValueCallable and move reference out of __callable.
Summary: In std::functional moves the reference out of the `__callable` implementation and replaces `_EnableIfCallable` with `_EnableIfLValueCallable` (`_EnableIfLValueCallable` passes `__callable` an lvalue reference type).

    Reviewers: ldionne, #libc!

    Subscribers: dexonsmith, libcxx-commits

    Tags: #libc

    Differential Revision: https://reviews.llvm.org/D80071
2020-05-19 17:15:28 -07:00
Michael Schellenberger Costa c579ab9962 [libcxx][type_traits] Add C++20 changes to common_type
Summary: This already implements the expected changes for LWG-3205

Reviewers: mclow.lists, EricWF, CaseyCarter, cjdb, #libc, ldionne

Reviewed By: #libc, ldionne

Subscribers: dexonsmith, broadwaylamb, christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D74350
2020-05-18 14:06:32 +02:00
Michael Schellenberger Costa ab9f11168f [libcxx][span] Implement solution to LWG-3255
This implements the relaxed requirements on the std::array constructors of span,
where the type only needs to be convertible to the element type of the span.

Note that the previous tests were not sufficient, as the const array<T, n> constructor
was only tested for compile time and the array<T, N> only during runtime.

Restructure the tests so that we can test conversions as well as both constructors.

Differential Revision: https://reviews.llvm.org/D75706
2020-05-14 10:50:44 -04:00
Michael Schellenberger Costa 79941086fb [libc++][span] SFINAE span default constructor on Extent == 0
The default constructor of a static span requires _Extent == 0 so
SFINAE it out rather than using a static_assert

Differential Revision: https://reviews.llvm.org/D71994
2020-05-14 09:35:07 -04:00
Michael Schellenberger Costa c5ff4031c6 [libcxx][span] Remove const_iterator from std::span
This implements the resolution to LWG-3320.

Differential Revision: https://reviews.llvm.org/D75642
2020-05-14 08:34:32 -04:00
Michael Schellenberger Costa c73a491d10 [libcxx][span] Remove tuple interface
This implements P2116 by removing the tuple interface from std::span.

Differential Revision: https://reviews.llvm.org/D75640
2020-05-14 08:25:49 -04:00
Michael Schellenberger Costa 6d2599e4f7 [libcxx][span] Implement P1976R2
This resolves the NB comment about the construction of a fixed-size span
from a dynamic range.

Differential Revision: https://reviews.llvm.org/D74577
2020-05-13 09:52:47 -04:00
Marek Kurdej ab61fe4150 Revert "[libc++] [LWG3321] Mark "year_month_day_last::day() specification does not cover !ok() values" issue as "Nothing to do", but add assertion."
This reverts commit e25a2601aa.
It was failing due to _LIBCPP_ASSERT throwing in a method marked noexcept.
2020-05-13 13:16:43 +02:00
Marek Kurdej e25a2601aa [libc++] [LWG3321] Mark "year_month_day_last::day() specification does not cover !ok() values" issue as "Nothing to do", but add assertion.
Summary:
This LWG issue states that the result of `year_month_day_last::day()` is implementation defined if `ok()` is `false`.
However, from user perspective, calling `day()` in this situation will lead to a (possibly difficult to find) crash.
Hence, I have added an assertion to warn user at least when assertions are enabled.
I am however not aware of the libc++ stand on the desired behaviour.

Reviewers: ldionne, mclow.lists, EricWF, #libc

Reviewed By: ldionne, #libc

Subscribers: christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D70346
2020-05-13 11:45:55 +02:00
zoecarver 8aa2266fd8 [libcxx] Constrain function assignment operator (2574).
This patch fixes LWG issue 2574.

Differential Review: https://reviews.llvm.org/D62928
2020-05-12 18:57:50 -07:00
zoecarver ce195fb22b [libcxx] Re-commit: shared_ptr changes from library fundamentals (P0414R2).
Implements P0414R2:
  * Adds support for array types in std::shared_ptr.
  * Adds reinterpret_pointer_cast for shared_ptr.

Re-committing now that the leaking tests are fixed.

Differential Revision: https://reviews.llvm.org/D62259
2020-05-12 11:23:18 -07:00
zoecarver 5eb55483eb Revert "[libcxx] shared_ptr changes from library fundamentals (P0414R2)."
This reverts commit e8c13c182a.
2020-05-11 22:43:17 -07:00
zoecarver e8c13c182a [libcxx] shared_ptr changes from library fundamentals (P0414R2).
Implements P0414R2:
  * Adds support for array types in std::shared_ptr.
  * Adds reinterpret_pointer_cast for shared_ptr.

Differential Revision: https://reviews.llvm.org/D62259
2020-05-11 18:46:29 -07:00
Eric Fiselier c490c5e81a Reland [libc++] Move abs and div into stdlib.h to fix header cycle.
This commit should will break libc++ without local submodule visibility, but
the LLVM+modules bots are now all using this mode. Before the Green Dragon
LLDB bot was failing to compile with a libc++ built with this commit as LSV
was disabled on macOS.

Original summary:

libc++ is careful to not fracture overload sets. When one overload
is visible to a user, all of them should be. Anything less causes
subtle bugs and ODR violations.

Previously, in order to support ::abs and ::div being supplied by
both <cmath> and <cstdlib> we had to do awful things that make
<math.h> and <stdlib.h> have header cycles and be non-modular.
This really breaks with modules.

Specifically the problem was that in C++ ::abs introduces overloads
for floating point numbers, these overloads forward to ::fabs,
which are defined in math.h. Therefore ::abs needed to be in math.h
too. But this required stdlib.h to include math.h and math.h to
include stdlib.h.

To avoid these problems the definitions have been moved to stddef.h
(which math includes), and the floating point overloads of ::abs
have been changed to call __builtin_fabs, which both Clang and GCC
support.
2020-05-08 21:52:27 +02:00
zoecarver 26466efe08 Revert "[libc++] ECMAScript IdentityEscape is ambiguous (2584)"
This reverts commit 6d2a66b10d.

The regex expressions in some lld tests need to be fixed. Reverting
until those are fixed.
2020-05-08 10:37:04 -07:00
zoecarver 6d2a66b10d [libc++] ECMAScript IdentityEscape is ambiguous (2584)
This patch fixes [[ https://cplusplus.github.io/LWG/issue2584 | 2584 ]]. Now the following works:
    const std::regex r1("\\z");
    assert(std::regex_match("z", r1));

Differential Revision: https://reviews.llvm.org/D66610
2020-05-07 14:26:25 -07:00
Marcel Hlopko c9e6519d15 Remove unused _LIBCPP_RAW_ITERATORS
Summary: This change removes seemingly unused _LIBCPP_RAW_ITERATORS.

Reviewers: #libc, EricWF, ldionne

Reviewed By: #libc, EricWF, ldionne

Subscribers: dexonsmith, ldionne, gribozavr2, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D79323
2020-05-07 22:26:15 +02:00
Antonio Sanchez aa0b991dcf [libc++] Fix ostream for complex numbers with fixed field width
The ostream operator<< is currently broken for std::complex with
specified field widths.

This patch a partial revert of c3478eff7a (reviewed as D71214),
restoring the correct behavior.

Differential Revision: https://reviews.llvm.org/D78816
2020-05-07 13:51:07 -04:00
Louis Dionne 31d41e3879 [libc++] Add tests for _LIBCPP_HAS_MERGED_TYPEINFO_NAMES_DEFAULT
The issue on Apple platforms was fixed in 2464d8135e, but this commit
adds some tests to make sure we don't regress.

See https://llvm.org/PR45549.

Differential Revision: https://reviews.llvm.org/D78963
2020-05-07 12:40:02 -04:00
Logan Smith 83564056d4 [libcxx] Add deduction guides for shared_ptr and weak_ptr
This patch adds deduction guides to <memory> to allow deducing
construction of shared_ptrs from unique_ptrs, and from weak_ptrs
and vice versa, as specified by C++17.

Differential Revision: https://reviews.llvm.org/D69603
2020-05-07 12:07:48 -04:00
Logan Smith 5b4a98eb58 [libcxx] Qualify make_pair in searcher implementations to prevent ADL
This patch adds `_VSTD::` to some calls to `make_pair` inside the
implementations of searchers, to prevent things exploding if there is
a make_pair in an associated namespace of a user-defined type.
https://godbolt.org/z/xAFG98

Differential Revision: https://reviews.llvm.org/D72640
2020-05-07 11:57:10 -04:00
Marek Kurdej 3e895085de [libc++][P1115][C++20] Improving the Return Value of Erase-Like Algorithms II: Free erase/erase if.
Summary:
This patch adds return type to std::erase and std::erase_if functions.

Also:
* Update __cpp_lib_erase_if to 202002L.
* Fix synopsis in unordered_map.
* Fix generate_feature_test_macro_components.py script.

Reviewers: EricWF, mclow.lists, ldionne, #libc

Reviewed By: ldionne, #libc

Subscribers: broadwaylamb, zoecarver, dexonsmith, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75905
2020-05-02 14:04:50 +02:00
Diogo Sampaio c14ac8043e [FIX][libc++][Regex] Using regex_constants match_prev_avail | match_not_bol | match_not_bow
Summary:
pr42199
When using regex_constants::match_prev_avail, it is defined that
--first is valid, and match_not_bol and match_not_bow should be
ignored. At the moment these flags are not ignored. This fixis that.

Reviewers: ldionne, miyuki, EricWF, mclow.lists, #libc

Reviewed By: ldionne, miyuki, #libc

Subscribers: broadwaylamb, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75622
2020-04-30 23:36:25 +01:00
Saleem Abdulrasool 88af3ddb1e build: update libc++ as there are some bots with integrated build
Some of the builders are building with C++ in the unified build.  Merge
this without review to try to restore the builder.
2020-04-28 20:07:28 +00:00
Raphael Isemann bd2965c9db Revert "Recommit [libc++] Move abs and div into stdlib.h to fix header cycle."
It seems that D74892 still hasn't fixed the issue on the bot. Currently
investigating the bot breakage and meanwhile (again) reverting this...
2020-04-28 20:23:22 +02:00
Eric Fiselier d0846b432c Recommit [libc++] Move abs and div into stdlib.h to fix header cycle.
This relands this commit as it broke the LLDB bot the first time it landed.
See also the discussion on https://reviews.llvm.org/rG82b47b2978405f802a33b00d046e6f18ef6a47be

Since D74892 this code should now also work on macOS.

Original description:

libc++ is careful to not fracture overload sets. When one overload
is visible to a user, all of them should be. Anything less causes
subtle bugs and ODR violations.

Previously, in order to support ::abs and ::div being supplied by
both <cmath> and <cstdlib> we had to do awful things that make
<math.h> and <stdlib.h> have header cycles and be non-modular.
This really breaks with modules.

Specifically the problem was that in C++ ::abs introduces overloads
for floating point numbers, these overloads forward to ::fabs,
which are defined in math.h. Therefore ::abs needed to be in math.h
too. But this required stdlib.h to include math.h and math.h to
include stdlib.h.

To avoid these problems the definitions have been moved to stddef.h
(which math includes), and the floating point overloads of ::abs
have been changed to call __builtin_fabs, which both Clang and GCC
support.
2020-04-28 15:42:36 +02:00
Louis Dionne f76c42416c [libc++] Improve the detection of whether the blocks runtime is available
The runtime for Blocks may not be available even though the Blocks
language extension _is_ available. Instead of potentially failing,
this commit is much more conservative and assumes the runtime for
Blocks is only provided on Apple platforms.

Differential Revision: https://reviews.llvm.org/D78757
2020-04-24 07:02:21 -04:00
Louis Dionne cd66970b37 [libc++] Don't try to include <Block.h> when not available 2020-04-22 15:22:12 -04:00
Louis Dionne 430b00954c [libc++] Add support for blocks in std::function
rdar://14390808
2020-04-22 14:58:02 -04:00
Dan Albert 75c4408653 Reland: Don't expose unavailable cstdio functions.
Marked unsupported for C++03 and C++11 since this test uses alias
declarations, and at least one C++03 bot was failing with
-Wc++11-extensions.

Change-Id: I8c3a579edd7eb83e0bc74e85d116b68f22400161
2020-04-16 12:51:08 -07:00
Louis Dionne 548d501082 [libc++] NFC: Reindent impossible to read conditional in __config 2020-04-16 15:02:03 -04:00
Louis Dionne 8079f8a7e8 [libc++] Simplify conditional in __config for _LIBCPP_NO_RTTI
We don't support GCC's older than 5.x anymore.
2020-04-16 12:51:30 -04:00
Martijn Vels 7ba045a430 Make basic_string::operator=() tail call properly
Summary: We discovered that the compiler may chose not to inline the operator=, which leads to an expensive extra stack frame. This change makes __assign_no_alias always tail called.

Reviewers: EricWF, #libc!

Subscribers: libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D77913
2020-04-10 19:41:46 -04:00
Eric Fiselier c6eb584c64 [libc++] Fix recursive instantiation in std::array.
The use of the `&& ...` fold expression in std::array's deduction guides
recursively builds a set of binary operator expressions of depth N where
`N` is the number of elements in the initializer.

This is problematic because arrays may be large, and instantiation
depth is limited.

This patch addresses the issue by flattening the SFINAE using
the existing `__all` type trait.
2020-04-09 17:42:10 -04:00
Eric Fiselier 601f763182 [libcxx] Adds [concept.same]
Patch from Christopher Di Bella (cjdb@google.com)
Reviewed as https://reviews.llvm.org/D74291

Adds `std::same_as` to libc++. Since there aren't clang-format rules for
//requires-expressions//, I'll need to disable the formatter in certain areas.
2020-04-08 18:00:13 -04:00
zoecarver b25ec45809 Fix __is_pointer builtin type trait to work with Objective-C pointer types.
Summary: 5ade17e broke __is_pointer for Objective-C pointer types. This patch fixes the builtin and re-applies the change to type_traits.

Tags: #clang, #libc

Differential Revision: https://reviews.llvm.org/D77519
2020-04-08 10:02:53 -07:00
Dan Albert 50280c1895 Revert "Don't expose unavailable cstdio functions."
Broke builders that emit different diagnostics. e.g.:

error: 'warning' diagnostics seen but not expected:
  Line 13: alias declarations are a C++11 extension
  Line 20: alias declarations are a C++11 extension

This reverts commit ff87813715.
2020-04-07 15:36:44 -07:00
Dan Albert ff87813715 Don't expose unavailable cstdio functions.
Summary: These aren't available on Android in all configurations.

Reviewers: EricWF, mclow.lists, #libc, ldionne

Reviewed By: EricWF, #libc, ldionne

Subscribers: broadwaylamb, dexonsmith, ldionne, krytarowski, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D76093
2020-04-07 15:02:30 -07:00
Louis Dionne 46c3876188 [libc++] Add availability markup for the C++20 Synchronization Library on Apple 2020-04-06 18:07:26 -04:00
Dan Albert cbf1904a3e Upstream Bionic definitions of ctype_base/regex.
Summary:
This is a patch that Android has been carrying in its tree for several
years. This patch upstreams the existing ABI.

There's some historical cruft here. __regex_word used to be a part of
regex_traits rather than ctype_base. Bionic also used to use its own
ctype implementation because the libc++ builtin one wasn't available
yet. Bionic's ctype masks were 8 bits wide and already saturated, so a
wider type needed to be used for the regex mask, and the existing
value was already used so Android needed to specify its own.

Since then Android has migrated to the builtin ctype implementation
and this patch probably should have been dropped then. Unfortunately
that was not noticed at the time, so now we need to keep this to
maintain the current ABI.

Reviewers: EricWF, #libc, ldionne

Reviewed By: #libc, ldionne

Subscribers: dexonsmith, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D76171
2020-04-06 13:38:16 -07:00
Joerg Sonnenberger 98f77828a9 Avoid using std::max_align_t in pre-C++11 mode
Always depend on the compiler to have a correct implementation of
max_align_t in stddef.h and don't provide a fallback. For pre-C++11,
require __STDCPP_NEW_ALIGNMENT__ in <new> as provided by clang in all
standard modes. Adjust test cases to avoid testing or using max_align_t
in pre-C++11 mode and also to better deal with alignof(max_align_t)>16.
Document requirements of the alignment tests around natural alignment of
power-of-two-sized types.

Differential revision: https://reviews.llvm.org/D73245
2020-04-04 01:38:41 +02:00
Louis Dionne 3d94f3060c [libc++] Fix is_pointer support for Objective-C++
This test regressed with 5ade17e0ca, but we never noticed it because
.pass.mm tests were skipped due to a bug in our Lit config. This commit
fixes is_pointer (by essentially reverting tha part of 5ade17e0ca) and
also adds .pass.mm tests to the list of supported test suffixes.

We can explore how to support __is_pointer with Objective-C++ qualifiers
as a follow-up -- the main goal of this commit is to fix the regression
quickly and make sure all tests of the suite are run.
2020-04-03 11:09:59 -04:00
zoecarver e6a39f00e8 [libcxx] Stop using builtin type traits for is_floating_point and is_arithmetic.
Based on an issue brought up in https://reviews.llvm.org/D67900, this commit reverts the changes to is_floating_point and  is_arithmetic made in D67900.

After D67900 landed, __float128 behaved differently in those two type traits, causing compiler errors in numeric limits (and possibly others).
2020-04-01 16:57:08 -07:00
Louis Dionne e9271a494f Remove legacy CMake targets for libcxx and libcxxabi
We've been meaning to remove those targets for a while, and the fix is
simple enough cause they're all just aliases to other targets.

This is a re-application of f383fb40b1, wich was reverted in 04d48111b
because the build bots had not been updated yet. The build bot configurations
have now been updated not to use the deprecated targets, and I verified
that they were using the non-deprecated targets, so we should be good
unless I missed a bot.

Differential Revision: https://reviews.llvm.org/D76104
2020-03-30 09:45:21 -04:00
Louis Dionne 04d48111bf Revert "Remove legacy CMake targets for libcxx and libcxxabi"
This reverts commit f383fb40b. It looks like several of our build bots
are still using the legacy target names, so we'll change those before
we commit this change again.
2020-03-23 11:03:00 -04:00
Louis Dionne f383fb40b1 Remove legacy CMake targets for libcxx and libcxxabi
We've been meaning to remove those targets for a while, and the fix is
simple enough cause they're all just aliases to other targets.

There's no doubt this commit will break some CI systems, however the
fix is trivial.

Differential Revision: https://reviews.llvm.org/D76104
2020-03-23 10:51:23 -04:00
zoecarver 9e2207a00b [libc++] fix non-builtin is_void implementation
Add the missing closing angle bracket to the call to remove_cv. This is only used when we can't use the builtin implementation.

Fixes: 5ade17e0ca
2020-03-19 11:25:41 -07:00
zoecarver 74494d9992 [libc++] Don't use __is_fundamental in C++03 mode
In C++03 mode, nullptr is defined by libc++, not the compiler so, we can't use __is_fundamental (because it will return false for nullptr).

Fixes: 5ade17e0ca
2020-03-19 10:48:52 -07:00
zoecarver 5ade17e0ca [libc++] Use builtin type traits whenever possible
This patch updates <type_traits> to use builtin type traits whenever
possible to improve compile times.

Differential Revision: https://reviews.llvm.org/D67900
2020-03-19 09:54:53 -07:00
Yunlian Jiang 30ccc2e8d2 [libc++] Add missing visibility annotation for __base
Differential Revision: https://reviews.llvm.org/D48680
2020-03-18 17:16:00 -04:00
Atmn Patel 51b78a3e06 [libc++] Bugfix to std::binomial_distribution<int>
The current implementation of binomial_distribution is not guaranteed to
converge for certain extreme configurations of the engine and distribution.
This is due to a mistake in the implementation of the algorithm from the
given reference paper. The algorithm in the paper is guaranteed to
terminate but has redundant statements. The current implementation
simplified away the redundancy into a while loop, but it excludes the
return condition of the case where a good sample cannot be returned for
the particular sample being used from the uniform distribution, which is
what causes the infinite loop. This change guarantees termination by
recognizing that a good sample cannot be returned and returning 0 after
breaking the loop. This is also in contrast to the paper because the
return value as specified in the paper violates basic checks in at least
a subset of the extreme cases where the current implementation fails to
terminate. This default return value of 0 is satisfactory for the
extreme case known so far.

Since this is only meant to affect extreme cases where the algorithm
does not terminate anyways, the behavior is expected to remain exactly
the same for all non-extreme cases that have been terminating so far.

Fixes https://llvm.org/PR44847

Differential Revision: https://reviews.llvm.org/D74997
2020-03-17 15:56:16 -04:00
Dimitry Andric 585a3cc31b Fix -Wdeprecated-copy-dtor and -Wdeprecated-dynamic-exception-spec warnings.
Summary:
The former are like:

libcxx/include/typeinfo:322:11: warning: definition of implicit copy constructor for 'bad_cast' is deprecated because it has a user-declared destructor [-Wdeprecated-copy-dtor]
  virtual ~bad_cast() _NOEXCEPT;
          ^
libcxx/include/typeinfo:344:11: note: in implicit copy constructor for 'std::bad_cast' first required here
    throw bad_cast();
          ^

Fix these by adding an explicitly defaulted copy constructor.

The latter are like:

libcxx/include/codecvt:105:37: warning: dynamic exception specifications are deprecated [-Wdeprecated-dynamic-exception-spec]
    virtual int do_encoding() const throw();
                                    ^~~~~~~

Fix these by using the _NOEXCEPT macro instead.

Reviewers: EricWF, mclow.lists, ldionne, #libc

Reviewed By: EricWF, #libc

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D76150
2020-03-17 18:59:54 +01:00
Marek Kurdej 05343588e3 [libc++] [P0646] Add feature-test macro for __cpp_lib_list_remove_return_type.
Summary: The return type modification has already been implemented in rL364840 and rL365290.

Reviewers: ldionne, mclow.lists, EricWF, #libc!

Reviewed By: ldionne

Subscribers: christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D70275
2020-03-12 11:06:49 +01:00
Louis Dionne a13417352a [libc++] Properly mark std::function as deprecated in C++03
Due to Clang bug http://llvm.org/PR45151, deprecated attributes are not
picked up on partial specializations. This patch instead applies it to
the first declaration of std::function itself.
2020-03-10 17:45:39 -04:00
Martijn Vels b019c5c037 Partially inline basic_string copy constructor in UNSTABLE
Summary:
    This is a recommit of https://reviews.llvm.org/D73223 where the added function accidentally ended up inside an idef block.

    This change splits the copy constructor up inlining short initialization, and explicitly outlining long initialization into __init_copy_ctor_external() which is the externally instantiated slow path.

    For unstable ABI, this has the following changes:

    remove basic_string(const basic_string&)
    remove basic_string(const basic_string&, const Allocator&)
    add __init_copy_ctor_external(const value_type*, size_type)
    Quick local benchmark for Copy:

    Master
    ```
    ---------------------------------------------------------------
    Benchmark                    Time             CPU   Iterations
    ---------------------------------------------------------------
    BM_StringCopy_Empty       3.50 ns         3.51 ns    199326720
    BM_StringCopy_Small       3.50 ns         3.51 ns    199510016
    BM_StringCopy_Large       15.7 ns         15.7 ns     45230080
    BM_StringCopy_Huge        1503 ns         1503 ns       464896
    ```
    With this change
    ```
    ---------------------------------------------------------------
    Benchmark                    Time             CPU   Iterations
    ---------------------------------------------------------------
    BM_StringCopy_Empty       1.99 ns         2.00 ns    356471808
    BM_StringCopy_Small       3.29 ns         3.30 ns    203425792
    BM_StringCopy_Large       13.3 ns         13.3 ns     52948992
    BM_StringCopy_Huge        1472 ns         1472 ns       475136
    ```

    Subscribers: libcxx-commits

    Tags: #libc

    Differential Revision: https://reviews.llvm.org/D75639
2020-03-04 17:52:46 -05:00
Martijn Vels 3712edb152 Revert "Partially inline basic_string copy constructor in UNSTABLE"
This reverts commit 8cf76e913b.

We are investigating why this causes compilation issues under -O3
2020-03-04 14:52:17 -05:00
Louis Dionne c030ba64e4 [libc++] Avoid deprecation warning in the implementation of __has_rebind 2020-03-04 14:38:51 -05:00
Eric Fiselier 5891e7302f [libc++] Move std::string extern template declarations to end of class.
They need to appear before any member functions are ODR used, because
they change the visibility of many of these functions and otherwise
they could end up with hidden visibility in the DSO.
2020-03-04 13:57:29 -05:00
Louis Dionne 30cbdcb5c3 [libc++] Revert to previous implementation of __has_rebind
The new implementation introduced in 5b1e5b43 broke the bot running GCC 5.
2020-03-04 13:55:35 -05:00
Michael Park 5b1e5b4338 [libc++][P0174] Deprecated/removed parts of default allocator.
Differential Revision: https://reviews.llvm.org/D70117
2020-03-04 12:06:26 -05:00
Martijn Vels 8cf76e913b Partially inline basic_string copy constructor in UNSTABLE
his change splits the copy constructor up inlining short initialization, and explicitly outlining long initialization into __init_copy_ctor_external() which is the externally instantiated slow path.

For unstable ABI, this has the following changes:

remove basic_string(const basic_string&)
remove basic_string(const basic_string&, const Allocator&)
add __init_copy_ctor_external(const value_type*, size_type)
Quick local benchmark for Copy:

Master
```
---------------------------------------------------------------
Benchmark                    Time             CPU   Iterations
---------------------------------------------------------------
BM_StringCopy_Empty       3.50 ns         3.51 ns    199326720
BM_StringCopy_Small       3.50 ns         3.51 ns    199510016
BM_StringCopy_Large       15.7 ns         15.7 ns     45230080
BM_StringCopy_Huge        1503 ns         1503 ns       464896
```

```
---------------------------------------------------------------
Benchmark                    Time             CPU   Iterations
---------------------------------------------------------------
BM_StringCopy_Empty       1.99 ns         2.00 ns    356471808
BM_StringCopy_Small       3.29 ns         3.30 ns    203425792
BM_StringCopy_Large       13.3 ns         13.3 ns     52948992
BM_StringCopy_Huge        1472 ns         1472 ns       475136
```

Author: Martijn Vels <martijn.vels@gmail.com>

Reviewers: EricWF, mclow.list

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73223
2020-03-03 17:49:25 -05:00
Martijn Vels 675326466b Add flag _LIBCPP_ABI_STRING_OPTIMIZED_EXTERNAL_INSTANTIATIONS for basic_string ABI
Summary: This review is a mostly trivial change to use an explicit ABI flag for the unstable external template list. This follows the practice for an ABI flag per feature, and provides a spot for the rational / motivation for the flag.

Reviewers: EricWF, ldionne

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75457
2020-03-02 10:26:37 -05:00
Martijn Vels f87d30cba2 Partially inline basic_string::operator=(const basic_string&)
Summary:
This change partially inlines operator=(const basic_string&) where both the input and current instance are short strings, making the assignment a fixed length inlined memcpy.

Assignments where either of the strings are long are delegate to __assign_no_alias<__is_short>(), which is templated for the long / short branch already observed in the caller.

Stable:
```
--------------------------------------------------------------------------------
Benchmark                                     Time             CPU   Iterations
--------------------------------------------------------------------------------
BM_StringAssignStr_Empty_Opaque            2.65 ns         2.66 ns    263745536
BM_StringAssignStr_Empty_Transparent       2.95 ns         2.96 ns    236494848
BM_StringAssignStr_Small_Opaque            2.93 ns         2.94 ns    237301760
BM_StringAssignStr_Small_Transparent       2.69 ns         2.69 ns    265809920
BM_StringAssignStr_Large_Opaque            19.6 ns         19.6 ns     35573760
BM_StringAssignStr_Large_Transparent       19.1 ns         19.1 ns     36716544
BM_StringAssignStr_Huge_Opaque             1901 ns         1901 ns       364544
BM_StringAssignStr_Huge_Transparent        1889 ns         1889 ns       360448
```

Unstable
```
--------------------------------------------------------------------------------
Benchmark                                     Time             CPU   Iterations
--------------------------------------------------------------------------------
BM_StringAssignStr_Empty_Opaque            1.29 ns         1.29 ns    540454912
BM_StringAssignStr_Empty_Transparent       1.11 ns         1.12 ns    628482048
BM_StringAssignStr_Small_Opaque            1.29 ns         1.29 ns    541216768
BM_StringAssignStr_Small_Transparent       1.11 ns         1.11 ns    629469184
BM_StringAssignStr_Large_Opaque            15.6 ns         15.6 ns     44945408
BM_StringAssignStr_Large_Transparent       14.9 ns         14.9 ns     46764032
BM_StringAssignStr_Huge_Opaque             1713 ns         1713 ns       401408
BM_StringAssignStr_Huge_Transparent        1704 ns         1704 ns       397312

```

Subscribers: libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75211
2020-03-02 09:58:11 -05:00
ogiroux 621388468b Some fixes for open breaks on MacOS and UBSan 2020-02-26 20:51:19 -08:00
Louis Dionne a0ec111c92 [libc++] Temporarily disable availability markup for the C++20 Synchronization library
The markup wasn't quite right, and that broke compilation with availability
markup enabled. I'm disabling it until I have time to fix it properly to
get the CI mostly green again.
2020-02-26 19:10:27 -05:00
Martijn Vels d260ea7199 Inline basic_string::erase for fastpath where __n == npos
Summary:
This change checks for the case where people want to erase a string to the end, i.e., __n == npos, and inlines the call if so.

This also demonstrates keeping the ABI intact for V1, but inlining the erase() method for unstable.

Reviewers: EricWF, mclow.lists, ldionne

Reviewed By: EricWF, ldionne

Subscribers: smeenai, dexonsmith, christof, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D73743
2020-02-26 13:37:45 -05:00
Mikhail Maltsev 14aef5367d [libcxx] Fix _LIBCPP_HAS_THREAD_API_EXTERNAL build
Summary:
The definition of `__libcpp_timed_backoff_policy` and the declaration of
`__libcpp_thread_poll_with_backoff` must not be guarded by
  #if !defined(_LIBCPP_HAS_THREAD_API_EXTERNAL)
because the definitions of `__libcpp_timed_backoff_policy::operator()`
and `__libcpp_thread_poll_with_backoff` aren't guarded by this macro
(and this is correct because these two functions are implemented in
terms of other libc++ functions and don't interact with the host
threading library).

Reviewers: ldionne, __simt__, EricWF, mclow.lists

Reviewed By: ldionne

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75191
2020-02-26 17:54:43 +00:00
Martijn Vels 07eb82fc06 Add _LIBCPP_BUILTIN_CONSTANT_P support.
Summary:
This change adds the macros _LIBCPP_COMPILER_HAS_BUILTIN_CONSTANT and _LIBCPP_BUILTIN_CONSTANT_P to detect compile time constants, and optimze the code accordingly.

A planned usage example:
The implementation of basic_string::assign() can short-cut a compile time known short string assignent into a fast and compact inlined assignment:

```
basic_string::assign(const value_type* __s) {
  if (_LIBCPP_BUILTIN_CONSTANT_P(__s[0]) && length(__s) < __min_cap) {
    copy(pointer(), _s, length(__s) + 1);
    set_size(length(__s));
  } else {
    // delegate / tail call out of line implementation
  }
}
```

Subscribers: christof, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D73732
2020-02-26 11:03:51 -05:00
zoecarver 28d38a25e9 Remove std::shared_ptr::allocate_shared
std::shared_ptr::allocate_shared isn't in the standard. This commit removes it from libc++. It updates std::allocate_shared to use __create_with_cntrl_block.

Differential Revision: https://reviews.llvm.org/D66178
2020-02-25 16:50:57 -08:00
Louis Dionne 3b5530cf96 [libc++] Avoid including <semaphore.h> on Apple
It turns out that <semaphore.h> is not well-behaved, as it transitively
includes <sys/param.h>, and that one defines several non-reserved macros
that clash with some downstream projects in modular builds. For the time
being, using <sys/semaphore.h> instead gives us the declarations we need
without the macros.

rdar://59744472
2020-02-25 17:52:34 -05:00
Martin Storsjö e3add3e5a1 [libcxx] Fix building for windows after 54fa9ecd30
Move the implementation of __libcpp_thread_poll_with_backoff
and __libcpp_timed_backoff_policy::operator() out of the
_LIBCPP_HAS_THREAD_API_PTHREAD block. None of the code in these
methods is pthreads specific.

Also add "inline _LIBCPP_INLINE_VISIBILITY" to
__libcpp_timed_backoff_policy::operator(), to avoid errors due to
multiple definitions of the operator. Contrary to
__libcpp_thread_poll_with_backoff (which is a template function),
this is a normal non-templated method.

Differential Revision: https://reviews.llvm.org/D75102
2020-02-25 21:33:52 +02:00
Louis Dionne 7c2f4a8370 [libc++] Revert 03dd205c15 "Adjust max_align_t handling"
That commit was made without approval from a libc++ reviewer, and it
also broke the build in C++03 mode.
2020-02-25 11:42:08 -05:00
Louis Dionne ab41129b1e [libc++] Proper fix for libc++'s modulemap after D68480
Summary:
In libc++, we normally #ifdef out header content instead of #erroring
out when the Standard in use is insufficient for the requirements of
the header.

Reviewers: EricWF

Subscribers: jkorous, dexonsmith, libcxx-commits, teemperor

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75074
2020-02-25 11:31:10 -05:00
Joerg Sonnenberger 03dd205c15 Adjust max_align_t handling
Depend on the compiler to provide a correct implementation of
max_align_t. If __STDCPP_NEW_ALIGNMENT__ is missing and C++03 mode has
been explicitly enabled, provide a minimal fallback in <new> as
alignment of the largest primitive types.
2020-02-25 01:36:43 +01:00
Raphael Isemann b61e83eb0e [libc++] Give headers that require C++14 a cplusplus14 requires in the modulemap
https://reviews.llvm.org/D68480 added those headers and made the std module
only usable with C++14 or later as the submodules were not marked as requiring
C++14 or later. This just adds the missing requires directives.
2020-02-24 20:20:55 +01:00
Louis Dionne b21405d1cd [libc++] Fix CI and Linux failures after landing D68480
- Avoid using C++11-and-later features in <atomic>:
  Historically, we've supported <atomic> in C++03, so we can't use C++11
  features in that header. This is something we really need to change,
  since our implementation of <atomic> is starting to accumulate technical
  debt because of that.
- Mark a test as unsupported on single threaded systems
- Add missing symbols to the Linux ABI list
2020-02-24 11:58:25 -05:00
Louis Dionne c008716417 [libc++] Mark the C++03 version of std::function as deprecated
Summary: We want to eventually remove it.

Reviewers: EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D74719
2020-02-24 10:59:58 -05:00
Louis Dionne 80e73f2295 [libc++] Adapt a few things around the implementation of P1135R6
- Add the new symbols to the ABI list on Darwin
- Add XFAIL markup to the tests that require dylib support on older platforms
- Add availability markup for back-deployment
2020-02-24 10:59:35 -05:00
Olivier Giroux 54fa9ecd30 [libc++] Implementation of C++20's P1135R6 for libcxx
Differential Revision: https://reviews.llvm.org/D68480
2020-02-24 10:59:35 -05:00
Martijn Vels d8969a1cb9 Split _LIBCPP_STRING_EXTERN_TEMPLATE_LIST up into a V1 and UNSTABLE version.
This change splits the _LIBCPP_STRING_EXTERN_TEMPLATE_LIST up into a _LIBCPP_STRING_V1_EXTERN_TEMPLATE_LIST containing the stable ABI, and a _LIBCPP_STRING_UNSTABLE_EXTERN_TEMPLATE_LIST containing the unstable ABI.

The purpose is to explicitly define and maintain the two lists, where the unstable ABI allows for ABI breaking changes for purposes such as optimization while offering a strong guarantee that any change inside the unstable ABI does not affect the stable ABI.

As per the comment in the __string header, we do still allow etries to be added to the stable ABI list as the c++ versions and corresponding c++ std API changes.
2020-02-20 23:21:14 -05:00
Mark de Wever 72ce0c8073 [libc++][regex] Validate backreferences in the constructor.
This patch enables throwing exceptions for invalid backreferences
in the constructor when using the basic, extended,  grep, or egrep grammar.

This fixes bug 34297.

Differential Revision: https://reviews.llvm.org/D62453
2020-02-20 18:16:21 -05:00
Logan Smith 092a57f508 [libc++] Fix unqualified call to 'ref' inside shared_ptr(unique_ptr<U, D>)
This prevents unintended ADL: https://gcc.godbolt.org/z/EHw3Gy
This issue was mentioned as an addendum in PR44398.

Differential Revision: https://reviews.llvm.org/D74289
2020-02-20 12:24:40 -05:00
Logan Smith e442f38395 [libc++] Fix unintended ADL inside ref(reference_wrapper<T>) and cref(reference_wrapper<T>)
This patch qualifies calls to ref and cref inside ref(reference_wrapper<T>)
and cref(reference_wrapper<T>), respectively. These previously unqualified
calls could break in the presence of user functions called ref/cref inside
associated namespaces: https://gcc.godbolt.org/z/8VfprT

Fixes PR44398.

Differential Revision: https://reviews.llvm.org/D74287
2020-02-20 12:22:21 -05:00
Louis Dionne c3478eff7a [libc++] reduce <complex> parsing time
Instead of including <ios> for ios_base::failbit, simply get failbit
member of the template argument. Print directly to a stream instead
of using intermediate ostringstream.

    Parsing time: 874ms -> 164ms (-81%)

Thanks to Nikita Kniazev for the patch!

Differential Revision: https://reviews.llvm.org/D71214
2020-02-19 16:09:41 -05:00
Louis Dionne 6ba2d7b166 [libc++] Fixes backreferences for extended grammar.
The regex backreferences were not properly parsed and used when using
the extended grammar. This change parses them. The issue was found while
working on PR34297.

Thanks to Mark de Wever for the patch!

Differential Revision: https://reviews.llvm.org/D62451
2020-02-19 15:57:16 -05:00
Eric Fiselier a829443cc7 [libc++] Fix ABI break in __bit_reference.
The libc++ __bit_iterator type has weird ABI calling conventions as a
quirk
of the implementation. The const bit iterator is trivial, but the
non-const
bit iterator is not because it declares a user-defined copy constructor.

Changing this now is an ABI break, so this test ensures that each type
is trivial/non-trivial as expected.

The definition of 'non-trivial for the purposes of calls':
  A type is considered non-trivial for the purposes of calls if:
      * it has a non-trivial copy constructor, move constructor, or
            destructor, or
	        * all of its copy and move constructors are deleted.
2020-02-19 12:02:06 -05:00
Raphael Isemann 23368bee15 Revert "[libc++] Move abs and div into stdlib.h to fix header cycle."
This reverts commit 82b47b2978.

This broke Clang and LLDB module builds without -fmodules-local-submodule-visbility.
I'll revert this for now until we have a fix and reland once Clang
can properly handle this code.

See also the discussion in https://reviews.llvm.org/rG82b47b2978405f802a33b00d046e6f18ef6a47be
2020-02-17 17:59:08 +01:00
Louis Dionne 8b60ba73af [libc++] Add availability markup for std::to_chars on Apple platforms
Summary:
Otherwise, one gets link errors when trying to back-deploy to older platforms.

rdar://problem/57854364

Reviewers: lichray, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D74626
2020-02-17 09:32:46 -05:00
Eric Fiselier 82b47b2978 [libc++] Move abs and div into stdlib.h to fix header cycle.
libc++ is careful to not fracture overload sets. When one overload
is visible to a user, all of them should be. Anything less causes
subtle bugs and ODR violations.

Previously, in order to support ::abs and ::div being supplied by
both <cmath> and <cstdlib> we had to do awful things that make
<math.h> and <stdlib.h> have header cycles and be non-modular.
This really breaks with modules.

Specifically the problem was that in C++ ::abs introduces overloads
for floating point numbers, these overloads forward to ::fabs,
which are defined in math.h. Therefore ::abs needed to be in math.h
too. But this required stdlib.h to include math.h and math.h to
include stdlib.h.

To avoid these problems the definitions have been moved to stddef.h
(which math includes), and the floating point overloads of ::abs
have been changed to call __builtin_fabs, which both Clang and GCC
support.
2020-02-15 18:55:07 -05:00
Eric Fiselier cccf1ef0c8 [libc++] Remove cycle between <type_traits> and <cstddef>
This was caused by byte depending on traits. This patch moves
the minimal amount of meta-programming into <cstddef> to break the cycle.
2020-02-14 17:36:27 +01:00
Eric Fiselier e337fb0790 add type_traits include as required for std::integral_constant 2020-02-14 16:38:28 +01:00
Louis Dionne 0a0e0afaa0 [libc++] span: Fix incorrect static asserts
The static asserts in span<T, N>::front() and span<T, N>::back() are
incorrect as they may be triggered from valid code due to evaluation
of a never taken branch:

    span<int, 0> foo;
    if (!foo.empty()) {
        auto x = foo.front();
    }

The problem is that the branch is always evaluated by the compiler,
creating invalid compile errors for span<T, 0>.

Thanks to Michael Schellenberger Costa for the patch.

Differential Revision: https://reviews.llvm.org/D71995
2020-02-14 14:32:41 +01:00
Louis Dionne b5abd50f06 [libc++] span: Guard against overflow in span::subspan
The calculation _Offset + _Count <= size() may overflow, so use
_Count <= size() - _Offset instead. Note that this is safe due to
the previous constraint that _Offset <= size().

Patch by Michael Schellenberger Costa.

Differential Revision: https://reviews.llvm.org/D71998
2020-02-12 16:21:46 +01:00
Louis Dionne 37f46650c3 [libc++] Make sure that vector copy-construction is disabled for non-copyable types
The Standard requires the value_type of the vector to be Cpp17CopyInsertable
in order for copy-construction to be enabled:

	http://eel.is/c++draft/container.requirements#tab:container.req

rdar://problem/56674564

Differential Revision: https://reviews.llvm.org/D74251
2020-02-11 17:12:16 +01:00
Louis Dionne 92a1f65f17 [libc++] span: Fix incorrect return type of span::subspan
The extent of the returned span was always std::dynamic_extent, which
is incorrect.

Thanks to Michael Schellenberger Costa for the patch.

Differential Revision: https://reviews.llvm.org/D71997
2020-02-11 11:58:45 +01:00
Louis Dionne b4a3e6b664 [libcxx] span: Remove unneeded comparison
size_t is always greater than 0, so remove the artifact from the old
index_type.

Patch by Michael Schellenberger Costa.

Differential Revision: https://reviews.llvm.org/D71996
2020-02-11 11:39:12 +01:00
Louis Dionne edbaa7fc04 [libc++] span: Cleanup includes
Thanks to Michael Schellenberger Costa for the patch.

Differential Revision: https://reviews.llvm.org/D72036
2020-02-11 11:17:30 +01:00
Louis Dionne 9fda213d62 [libcxx] Qualify make_move_iterator in vector::insert for input iterators
Unqualified calls to make_move_iterator in the vector::insert overload
for input iterators lead to ADL issues: https://gcc.godbolt.org/z/bmcNbh

Patch by Logan Smith.

Differential Revision: https://reviews.llvm.org/D74290
2020-02-11 11:00:45 +01:00
Louis Dionne 1ac44d9fd1 [libc++] Protect <span> against min/max macro
Patch by Corentin Jabot
Differential Revision: https://reviews.llvm.org/D73855
2020-02-10 13:41:34 +01:00
Marek Kurdej e93e58c6c4 Reland [libc++] [P0325] Implement to_array from LFTS with updates.
Fixed expected errors and notes.

Summary:
This patch implements https://wg21.link/P0325.

Reviewers: EricWF, mclow.lists, ldionne, lichray

Reviewed By: ldionne, lichray

Subscribers: lichray, dexonsmith, zoecarver, christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D69882
2020-01-31 11:47:18 +01:00
Marek Kurdej 5e7017273f Revert "[libc++] [P0325] Implement to_array from LFTS with updates."
This reverts commit 86aae78268.

A test is failing on "Release" build without assertions enabled (Fedora 31 on x86_64).
2020-01-31 09:45:50 +01:00
Martijn Vels 282b803b62 White space only change: reflow a comment in basic_string
Summary: This change reflows a comment line. This change serves as a no-op test commit

Reviewers: mclow.lists, ldionne, EricWF

Subscribers: dexonsmith, christof, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D73552
2020-01-30 19:55:48 -05:00
Marek Kurdej 86aae78268 [libc++] [P0325] Implement to_array from LFTS with updates.
Summary:
This patch implements https://wg21.link/P0325.
Please mind that at it is my first contribution to libc++, so I may have forgotten to abide to some conventions.

Reviewers: EricWF, mclow.lists, ldionne, lichray

Reviewed By: ldionne, lichray

Subscribers: lichray, dexonsmith, zoecarver, christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D69882
2020-01-30 13:38:37 +01:00
Dimitry Andric 5e416ba943 Define _LIBCPP_HAS_TIMESPEC_GET for FreeBSD when appropriate
Summary:
FreeBSD got `timespec_get` support somewhere in the 12.x timeframe, but
the C++ version check in its system headers was written incorrectly.
This has now been fixed for both FreeBSD 13 and 12.

Add checks for the corresponding `__FreeBSD_version` values, to define
`_LIBCPP_HAS_TIMESPEC_GET` when the function is supported.

Reviewers: emaste, EricWF, ldionne, mclow.lists

Reviewed By: ldionne

Subscribers: arichardson, krytarowski, christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D71522
2020-01-30 08:00:56 +01:00
Martin Storsjö 7db4f2c694 [libcxx] [Windows] Store the lconv struct returned from localeconv in locale_t
This fixes using non-default locales, which currently can crash when
e.g. formatting numbers.

Within the localeconv_l function, the per-thread locale is temporarily
changed with __libcpp_locale_guard, then localeconv() is called,
returning an lconv * struct pointer.

When localeconv_l returns, the __libcpp_locale_guard dtor restores
the per-thread locale back to the original. This invalidates the
contents of the earlier returned lconv struct, and all C strings
that are pointed to within it are also invalidated.

Thus, to have an actually working localeconv_l function, the
function needs to allocate some sort of storage for the returned
contents, that stays valid for as long as the caller needs to use
the returned struct.

Extend the libcxx/win32 specific locale_t class with storage for
a deep copy of a lconv struct, and change localeconv_l to take
a reference to the locale_t, to allow it to store the returned
lconv struct there.

This works fine for libcxx itself, but wouldn't necessarily be right
for a caller that uses libcxx's localeconv_l function.

This fixes around 11 of libcxx's currently failing tests on windows.

Differential Revision: https://reviews.llvm.org/D69505
2020-01-29 22:37:11 +02:00
David Zarzycki 5dda92fcb0
Add test for spaceship operator to __config
Summary:
The libcxx test suite auto-detects spaceship operator, but __config does not. This means that the libcxx test suite has been broken for over a month when using top-of-tree clang. This also really ought to be fixed before 10.0.

See: bc633a42dd

Reviewers: chandlerc, mclow.lists, EricWF, ldionne, CaseyCarter

Reviewed By: EricWF

Subscribers: broadwaylamb, hans, dexonsmith, tstellar, llvm-commits, libcxx-commits

Tags: #libc, #llvm

Differential Revision: https://reviews.llvm.org/D72980
2020-01-24 13:27:22 -05:00
Louis Dionne 8ae404a2f6 [libc++] Make sure std::is_scalar returns true for block types
Summary:
The compiler already treats them as scalar types, so the library should
too. Furthermore, this allows blocks to be used in more places, for
example in std::optional, which requires an object type.

rdar://problem/57892832

Reviewers: dexonsmith, EricWF, mclow.lists
Differential Revision: https://reviews.llvm.org/D72708
2020-01-21 17:15:15 -08:00
Eric Fiselier fa40b41168 Revert "[libc++] Optimize / partially inline basic_string copy constructor"
This reverts commit a8a9c8e0a1.

There are multiple reported failures caused by this change.
Each failure is really weird, but it makes sense to revert
while investigating.
2020-01-20 21:41:58 -05:00
Eric Fiselier a8a9c8e0a1 [libc++] Optimize / partially inline basic_string copy constructor
Splits copy constructor up inlining short initialization, outlining long
initialization into __init_long() which is the externally instantiated slow
path initialization.

Subsequently changing the copy ctor to be inlined (not externally instantiated)
provides significant speed ups for short string initialization.

Generated code given:

void StringCopyCtor(void* mem, const std::string& s) {
    std::string*p = new(mem) std::string{s};
}

asm:
        cmp     byte ptr [rsi + 23], 0
        js      .LBB0_2
        mov     rax, qword ptr [rsi + 16]
        mov     qword ptr [rdi + 16], rax
        movups  xmm0, xmmword ptr [rsi]
        movups  xmmword ptr [rdi], xmm0
        ret
.LBB0_2:
        jmp     std::basic_string::__init_long # TAILCALL

Benchmark:
BM_StringCopy_Empty                                           5.19ns ± 6%             1.50ns ± 8%  -71.02%        (p=0.000 n=10+10)
BM_StringCopy_Small                                           5.14ns ± 8%             1.53ns ± 7%  -70.17%        (p=0.000 n=10+10)
BM_StringCopy_Large                                           18.9ns ± 0%             19.3ns ± 0%   +1.92%        (p=0.000 n=10+10)
BM_StringCopy_Huge                                             309ns ± 1%              316ns ± 5%     ~            (p=0.633 n=8+10)

Patch from Martijn Vels (mvels@google.com)
Reviewed as D72160.
2020-01-17 16:53:54 -05:00
Petr Hosek 9050d0fb59 [libcxx] Temporarily switch back to pthread backend for Fuchsia
We switched to C11 thread API on Fuchsia in ab9aefe, but further
testing showed that Fuchsia's C11 mutex implementation needs a few
improvements for this to be usable, so we temporarily switch back
to the pthread implementation until those issues are addressed.

Differential Revision: https://reviews.llvm.org/D72862
2020-01-16 14:53:08 -08:00
Eric Fiselier 59919c4d6b [libc++] Fix Windows DLL build for string.
We need to mark string::npos with _LIBCPP_FUNC_VIS on the first
in-class declaration, otherwise it might get ignored
2020-01-16 15:01:12 -05:00
Petr Hosek 3481e5d7ed [libcxx] Use mtx_plain | mtx_recursive following C11 API
The C11 API specifies that to initialize a recursive mutex,
mtx_plain | mtx_recursive should be used with mtx_init.

Differential Revision: https://reviews.llvm.org/D72809
2020-01-15 15:15:39 -08:00
Eric Fiselier 313d89724c [libc++] Fix parsing <string> in C++03.
Specifically, add a space between >> when closing templates.
2020-01-15 17:29:55 -05:00
Eric Fiselier 58c7fa5ade [libc++] Optimize basic_string::operator=(const basic_string&) for SSO assignments
This change optimizes the operator=() assignment for short strings by direcly
copying the raw data from the source into the current instance. This creates an
optimized / inlined mempcy up to over 2X faster for short string assignments.
With inlining enabled for operator=, performance is up to 6X faster.

Benchmarks 'as is':
name                                    old time/op   new time/op    delta
BM_StringAssignStr_Empty_Opaque         6.05ns ± 2%   3.59ns ± 0%  -40.67%
BM_StringAssignStr_Empty_Transparent    5.15ns ± 0%   3.08ns ± 0%  -40.12%
BM_StringAssignStr_Small_Opaque         7.71ns ± 0%   3.59ns ± 0%  -53.45%
BM_StringAssignStr_Small_Transparent    7.66ns ± 0%   3.09ns ± 0%  -59.66%
BM_StringAssignStr_Large_Opaque         24.1ns ± 0%   24.9ns ± 0%   +3.22%
BM_StringAssignStr_Large_Transparent    22.2ns ± 0%   22.8ns ± 0%   +2.77%
BM_StringAssignStr_Huge_Opaque           315ns ± 6%    320ns ± 5%     ~
BM_StringAssignStr_Huge_Transparent      318ns ± 5%    321ns ± 4%     ~

Benchmarks with partial inlining operator=():
name                                    old time/op   new time/op    delta
BM_StringAssignStr_Empty_Opaque         5.94ns ± 2%   1.95ns ± 0%  -67.21%
BM_StringAssignStr_Empty_Transparent    5.14ns ± 0%   1.04ns ± 1%  -79.73%
BM_StringAssignStr_Small_Opaque         7.69ns ± 0%   1.96ns ± 0%  -74.48%
BM_StringAssignStr_Small_Transparent    7.65ns ± 0%   1.04ns ± 0%  -86.40%
BM_StringAssignStr_Large_Opaque         24.1ns ± 0%   24.5ns ± 0%   +1.61%
BM_StringAssignStr_Large_Transparent    22.2ns ± 0%   21.1ns ± 0%   -4.70%
BM_StringAssignStr_Huge_Opaque           317ns ± 5%    323ns ± 4%     ~
BM_StringAssignStr_Huge_Transparent      318ns ± 5%    320ns ± 5%     ~

Patch by Martijn Vels (mvels@google.com)
Reviewed as https://reviews.llvm.org/D72704
2020-01-15 17:27:10 -05:00
Eric Fiselier 288a143639 [libc++] Explicitly enumerate std::string external instantiations - Attempt 2
The GCC build failures have been addressed, and the LLDB failures were
  fixed by LLDB.

   I have also verified that the apple-clang 9.0 segfault no longer
   occurs.

Original Message:

 The external instantiation of std::string is a problem for libc++.
    Additions and removals of inline functions in string can cause ABI
    breakages, including introducing new symbols.

    This patch aims to:
      (1) Make clear which functions are explicitly instatiated.
      (2) Prevent new functions from being accidentally instantiated.
      (3) Allow a migration path for adding or removing functions from the
      explicit instantiation over time.

    Although this new formulation is uglier, it is preferable from a
    maintainability and readability standpoint because it explicitly
    enumerates the functions we've chosen to expose in our ABI. Changing
    this list is non-trivial and requires thought and planning.

    (3) is achieved by making it possible to control the extern template declaration
    separately from it's definition. Meaning we could add a new definition to
    the dylib, wait for it to roll out, then add the extern template
    declaration to the header. Similarly, we could remove existing extern
    template declarations while still keeping the definition to prevent ABI
    breakages.
2020-01-15 17:12:49 -05:00
Eric Fiselier 2d8f23f571 [libc++] Explicitly mark basic_string<...>::npos with default
visibility.

This ensures that the version compiled into the library isn't
accidentally hidden.
2020-01-15 17:02:17 -05:00
Eric Fiselier 24d2a015ea [libc++] Make SFINAE'd member functions in string mutually exclusive.
This patch is needed in order to work around a GCC bug that fails to
explicitly instantiate a non-template function of a class template when
there is another overload that's a function template.
(See https://godbolt.org/z/4bUQ_b)

This patch SFINAE's away the function templates when the argument is
a basic_string.
2020-01-15 17:00:26 -05:00
Hans Wennborg 5852475e2c Bump the trunk major version to 11
and clear the release notes.
2020-01-15 13:38:01 +01:00
Petr Hosek ab9aefee9f [libcxx] Use C11 thread API on Fuchsia
On Fuchsia, pthread API is emulated on top of C11 thread API. Using C11
thread API directly is more efficient.

While this implementation is only used by Fuchsia at the moment, it's
not Fuchsia specific, and could be used by other platforms that use C11
threads rather than pthreads in the future.

Differential Revision: https://reviews.llvm.org/D64378
2020-01-14 16:48:20 -08:00
Martin Storsjö 337e435964 [libcxx] [Windows] Make a more proper implementation of strftime_l for mingw with msvcrt.dll
This also makes this function consistent with the rest of the
libc++ provided fallbacks.

The locale support in msvcrt.dll is very limited anyway; it can
only be configured processwide, not per thread, and it only seems
to support the locales "C" and "" (the user set locale), so it's
hard to make any meaningful automatic test for it. But manually tested,
this change does make time formatting locale code in libc++ output
times in the user requested format, when using locale "".

Differential Revision: https://reviews.llvm.org/D69554
2020-01-14 22:29:47 +02:00
Oliver Stannard 6a634a5dba Revert "[libc++] Explicitly enumerate std::string external instantiations."
This is causing failures for multiple buildbots and bootstrap builds,
details at https://reviews.llvm.org/rG61bd1920.

This reverts commit 61bd19206f.
2020-01-13 13:54:04 +00:00
Eric Fiselier 61bd19206f [libc++] Explicitly enumerate std::string external instantiations.
The external instantiation of std::string is a problem for libc++.
    Additions and removals of inline functions in string can cause ABI
    breakages, including introducing new symbols.

    This patch aims to:
      (1) Make clear which functions are explicitly instatiated.
      (2) Prevent new functions from being accidentally instantiated.
      (3) Allow a migration path for adding or removing functions from the
      explicit instantiation over time.

    Although this new formulation is uglier, it is preferable from a
    maintainability and readability standpoint because it explicitly
    enumerates the functions we've chosen to expose in our ABI. Changing
    this list is non-trivial and requires thought and planning.

    (3) is achieved by making it possible to control the extern template declaration
    separately from it's definition. Meaning we could add a new definition to
    the dylib, wait for it to roll out, then add the extern template
    declaration to the header. Similarly, we could remove existing extern
    template declarations while still keeping the definition to prevent ABI
    breakages.
2020-01-09 15:51:02 -05:00
Kazuaki Ishizaki 9de6a39872 [libcxx] fix incorrect attribute property
Summary:
`__has_attribute(fallthough)` -> `__has_attribute(fallthrough)`
This is a follow-up of https://reviews.llvm.org/D72287

Reviewers: EricWF, mclow.lists, Jim

Reviewed By: Jim

Subscribers: christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D72314
2020-01-08 09:35:26 +08:00
Ruslan Baratov 6e8659c351 [libc++] Fix typo in std::midpoint
Reviewed By: mclow.lists

Differential Revision: https://reviews.llvm.org/D71525
2019-12-21 01:26:24 -08:00
Michał Górny e1882af9f6 [libc++] Update feature list for NetBSD
Add NetBSD to the same feature list as Fuchsia since it matches
in available features, effectively enabling aligned_alloc(),
timespec_get() and C11 features.  Remove now-duplicate declaration
of quick_exit() support.

Differential Revision: https://reviews.llvm.org/D71511
2019-12-20 17:50:47 +01:00
Eric Fiselier a53534a9f6 [libc++] Add __default_init_tag to basic_string constructors
This removes unneeded zero initialization of string data.

For example, given the below code:

void Init(void *mem) {
    new (mem) std::string("Hello World");
}

Assembly before:

Init(void*):
        xorps   xmm0, xmm0
        movups  xmmword ptr [rdi], xmm0
        mov     qword ptr [rdi + 16], 0
        mov     byte ptr [rdi], 22
        movabs  rax, 8022916924116329800
        mov     qword ptr [rdi + 1], rax
        mov     dword ptr [rdi + 8], 1684828783
        mov     byte ptr [rdi + 12], 0
        ret

Assembly after:

Init():
        mov     byte ptr [rdi], 22
        movabs  rax, 8022916924116329800
        mov     qword ptr [rdi + 1], rax
        mov     dword ptr [rdi + 8], 1684828783
        mov     byte ptr [rdi + 12], 0
        ret

Patch by Martijn Vels (mvels@google.com)
Reviewed as https://reviews.llvm.org/D70621
2019-12-16 19:04:09 -05:00
Eric Fiselier 549545b64a [libc++] Rework compressed pair constructors.
This patch de-duplicates most compressed pair constructors
to use the same code in C++11 and C++03.

Part of doing that is deleting the "__second_tag()" and replacing
it with a "__value_init_tag()" which has the same effect, but
allows for the removal of the special "one-arg" first element
constructor.

This patch is intended to have no semantic change.
2019-12-16 18:38:58 -05:00
Eric Fiselier 0fa118a9da Add default initialization to compressed_pair.
This change introduces the __default_init_tag to memory, and a corresponding
element constructor to allow for default initialization of either of the pair
values. This is useful for classes such as std::string where most (all)
constructors explicitly initialize the values in the constructor.

Patch by Martijn Vels (mvels@google.com)
Reviewed as https://reviews.llvm.org/D70617
2019-12-16 17:14:02 -05:00
Eric Fiselier fda3825c7a [libc++] Ensure __config always defines certain configuration macros. 2019-12-13 15:42:07 -05:00
Eric Fiselier f97936fabd [libc++] Cleanup and enable multiple warnings.
Too many warnings are being disabled too quickly. Warnings are
important to keeping libc++ correct. This patch re-enables two
warnings: -Wconstant-evaluated and -Wdeprecated-copy.

In future, all warnings disabled for the test suite should require
an attached bug. The bug should state the plan for re-enabling that
warning, or a strong case why it should remain disabled.
2019-12-12 21:09:08 -05:00
Fangrui Song b7eb30d481 __bit_reference: fix -Wdeprecated-copy warnings
Since C++11, [depr.impldec]:

The implicit definition of a copy constructor as defaulted is deprecated
if the class has a user-declared copy assignment operator or a
user-declared destructor.

At clang HEAD, -Wdeprecated-copy (included by -Wextra) will warn on such instances.

Reviewed By: EricWF

Differential Revision: https://reviews.llvm.org/D71096
2019-12-12 16:31:36 -08:00
Eric Christopher fa0fc04a4f Temporarily Revert "[libc++] Fix -Wdeprecated-copy warnings in __bit_reference"
as it's causing test failures due to mismatched visibility.

This reverts commit 02bb20223b.
2019-12-12 00:22:37 -08:00
Eric Christopher 02bb20223b [libc++] Fix -Wdeprecated-copy warnings in __bit_reference
Add a couple of default copy constructors to fix the warning.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D71395
2019-12-11 23:50:28 -08:00
Louis Dionne dd37e24ae6 [libc++] Hide some functions and types in <future> and <thread> as hidden
Otherwise, weak symbols leak into user programs when using `async` with
non-internal types.
2019-12-10 19:19:45 -05:00
marshall 703c26f03b Optimize and fix basic_string move assignment operator. Reviewed as https://reviews.llvm.org/D68623. Thanks to mvels for the patch. 2019-11-27 07:13:32 -08:00
Shoaib Meenai d018b556c7 [libcxx] Omit unneeded locale fallbacks on Android 21+
Android API level 21 and above have all these functions available, so we
don't need to include our fallback definitions.

Differential Revision: https://reviews.llvm.org/D69983
2019-11-25 11:06:08 -08:00
Dan Albert 19fd9039ca Fix _LIBCPP_HAS_ definitions for Android.
Summary:
Android added quick_exit()/at_quick_exit() in API level 21,
aligned_alloc() in API level 28, and timespec_get() in API level 29,
but has the other C11 features at all API levels (since they're basically
just coming from clang directly).

_LIBCPP_HAS_QUICK_EXIT and _LIBCPP_HAS_TIMESPEC_GET already existed,
so we can reuse them. (And use _LIBCPP_HAS_TIMESPEC_GET in a few more
places where _LIBCPP_HAS_C11_FEATURES has been used as a proxy. This
isn't correct for Android.)

_LIBCPP_HAS_ALIGNED_ALLOC is added, to cover aligned_alloc() (obviously).

Add a missing std:: before aligned_alloc in a cstdlib test, and remove a
couple of !defined(_WIN32)s now that we're explicitly testing
TEST_HAS_ALIGNED_ALLOC rather than TEST_HAS_C11_FEATURES.

Reviewers: danalbert, EricWF, mclow.lists

Reviewed By: danalbert

Subscribers: srhines, christof, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D69929
2019-11-18 12:19:58 -08:00
Eric Fiselier f82dba0192 Rename __is_foo_iterator traits to reflect their Cpp17 nature.
With the upcoming introduction of iterator concepts in ranges,
the meaning of "__is_contiguous_iterator" changes drastically.

Currently we intend it to mean "does it have this iterator category",
but it could now also mean "does it meet the requirements of this
concept", and these can be different.
2019-11-18 01:49:32 -05:00
Eric Fiselier 6624fcba43 [libc++] Add _ITER_CONCEPT and _ITER_TRAITS implementations from C++20
These traits are currently unused because we don't implement ranges.
However, their addition is part of ongoing work to allow libc++
to optimize on user-provided contiguous iterators.
2019-11-16 20:26:35 -05:00
Eric Fiselier 45d048c204 [libc++] Add C++20 contiguous_iterator_tag.
This work is part of an ongoing effort to allow libc++ to
optimize user provided contiguous iterators.
2019-11-16 20:14:44 -05:00
Eric Fiselier 0068c59139 [libc++] Rename __to_raw_pointer to __to_address.
This function has the same behavior as the now-standand std::to_address.
Re-using the name makes the behavior more clear, and in the future it
will allow us to correctly get the raw pointer for user provided pointer
types.
2019-11-16 17:16:09 -05:00
Marek Kurdej 8e34be2f25 [libc++] [chrono] Fix year_month_weekday::ok() implementation.
Reviewers: ldionne, EricWF, mclow.lists

Reviewed By: mclow.lists

Subscribers: christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D70282
2019-11-15 18:48:45 +01:00
Ilya Tokar 767eadd782 [libcxx] use __builtin_isnan in std::isnan.
Summary: This allows std::isnan to be fully inlined, instead of generating calls.

Reviewers: EricWF

Reviewed By: EricWF

Subscribers: christof, ldionne

Differential Revision: https://reviews.llvm.org/D69806
2019-11-15 12:29:18 -05:00
Louis Dionne 1466335cf4 [libc++][P1872] span should have size_type, not index_type.
Thanks to Marek Kurdej for the patch.

Differential Revision: https://reviews.llvm.org/D70206
2019-11-14 09:07:05 -05:00
Louis Dionne 8b77a3a0f4 [libc++] [P1612] Add missing feature-test macro __cpp_lib_endian.
Thanks to Marek Kurdej for the patch.

Differential Revision: https://reviews.llvm.org/D70221
2019-11-14 08:55:19 -05:00
Michael Park eb8710cb93
[libc++][P0980] Marked member functions move/copy/assign of char_traits constexpr.
Reviewers: ldionne, EricWF, mclow.lists

Reviewed By: ldionne

Subscribers: christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D68840
2019-11-11 09:49:48 -08:00
Louis Dionne 48b7068bec [libc++] Mark __call_once_proxy as hidden and internal
We effectively never want to export that function, which is an
implementation detail of libc++. This was previously tried in
603715c66b and then reverted in 8335dd314f because it caused
linker warnings. These linker warnings should go away now that we
use internal_linkage instead of always_inline to implement per-TU
insulation.
2019-11-11 10:27:48 -05:00
Mark de Wever 27c4eaac8c [libc++] Validate the entire regex is consumed
This change would have warned about the bug found in D62451.
No unit tests since the exception should never throw.

Differential Revision: https://reviews.llvm.org/D62452
2019-11-09 17:01:37 +01:00
Louis Dionne 0ec6a4882e [libc++] Fix potential OOB in poisson_distribution
See details in the original Chromium bug report:
    https://bugs.chromium.org/p/chromium/issues/detail?id=994957
2019-11-07 13:29:40 +00:00
Louis Dionne 83901cbe5e [libc++] Fixed copy/copy_n/copy_backward for compilers that do not support is_constant_evaluated.
Differential Revision: https://reviews.llvm.org/D69940
2019-11-07 12:39:10 +00:00
Louis Dionne 13c90a5716 [libc++][P0202] Marked algorithms copy/copy_n/copy_if/copy_backward constexpr
Thanks to Michael Park for the patch.

Differential Revision: https://reviews.llvm.org/D68837
2019-11-06 12:02:41 +00:00
Jorg Brown 586952f4ce Optimize std::midpoint for integers
Same idea as the current algorithm, that is, add (half of the difference between a and b) to a.

But we use a different technique for computing the difference: we compute b - a into a pair of integers that are named "sign_bit" and "diff". We have to use a pair because subtracting two 32-bit integers produces a 33-bit result.

Computing half of that is a simple matter of shifting diff right by 1, and adding sign_bit shifted left by 31. llvm knows how to do that with one instruction: shld.

The only tricky part is that if the difference is odd and negative, then shifting it by one isn't the same as dividing it by two - shifting a negative one produces a negative one, for example. So there's one more adjustment: if the sign bit and the low bit of diff are one, we add one.

For a demonstration of the codegen difference, see https://godbolt.org/z/7ar3K9 , which also has a built-in test.

Differential Revision: https://reviews.llvm.org/D69459
2019-11-04 19:00:23 -08:00
Louis Dionne adadc665f8 [libc++] Add test and remove workaround for PR13592
PR13592 was caused by a problem in how to compiler implemented the
__is_convertible_to intrinsic. That problem, reported as PR13591,
was fixed back in 2012. We don't support such old versions of Clang
anyway, so we don't need the library workaround that had been added
to solve PR13592 (while waiting for the compiler fix).
2019-10-30 15:52:11 -07:00
David Blaikie e658b3eb97 PR43764: Qualify a couple of calls to forward_as_tuple to be ADL-resilient. 2019-10-28 18:04:41 -07:00
--global a062856bcf [NFC] Comment endif to test commit access 2019-10-28 09:19:08 -07:00
Louis Dionne 6b77ebdc91 [NFC] Strip trailing whitespace from libc++ 2019-10-23 11:19:19 -07:00
Casey Carter 689ce81059
[libc++][NFC] Remove excess trailing newlines from most files
Testing git commit access.
2019-10-23 08:08:57 -07:00
Zoe Carver 40c47680eb [libcxx] Remove shared_ptr::make_shared
Summary: This patch removes `shared_ptr::make_shared` as it is not part of the standard. This patch also adds __create_with_cntrl_block, which is a help function that can be used in std::allocate_shared and std::make_shared. This is the third patch (out of 4) from D66178.

    Reviewers: EricWF, mclow.lists, ldionne

    Subscribers: christof, dexonsmith, libcxx-commits

    Tags: #libc

    Differential Revision: https://reviews.llvm.org/D68805

llvm-svn: 375504
2019-10-22 15:16:49 +00:00
Louis Dionne 3292facc0a [NFC] Fix typos in CMake comment
llvm-svn: 375469
2019-10-21 23:38:32 +00:00
Dimitry Andric d5367db95c Refine check for `_LIBCPP_C_HAS_NO_GETS` on FreeBSD
Summary:
In D67316 we added `_LIBCPP_C_HAS_NO_GETS` to signal that the C library
does not provide `gets()`, and added a test for FreeBSD 13 or higher,
using the compiler-defined `__FreeBSD__` macro.

Unfortunately this did not work that well for FreeBSD's own CI process,
since the gcc compilers used for some architectures define `__FreeBSD__`
to match the build host, not the target.

Instead, we should use the `__FreeBSD_version` macro from the userland
header `<osreldate.h>`, which is more fine-grained.  See also
<https://reviews.freebsd.org/D22034>.

Reviewers: EricWF, mclow.lists, emaste, ldionne

Reviewed By: emaste, ldionne

Subscribers: dexonsmith, bsdjhb, krytarowski, christof, ldionne, libcxx-commits

Differential Revision: https://reviews.llvm.org/D69174

llvm-svn: 375340
2019-10-19 10:59:23 +00:00
Richard Smith a9727033fb P1152R4: Fix deprecation warnings in libc++ testsuite and in uses of is_invocable that would internally conjure up a deprecated function type.
Summary: The implementation of P1152R4 in Clang has resulted in some deprecation warnings appearing in the libc++ and libc++abi test suite. Fix or suppress these warnings.

Reviewers: mclow.lists, EricWF

Subscribers: christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D68879

llvm-svn: 375307
2019-10-19 00:06:00 +00:00
Eric Fiselier 78153b3a97 Optimize operator=(const basic_string&) for tail call.
Patch by Martijn Vels (mvels@google.com)
Reviewed as https://reviews.llvm.org/D68276

This is a non trivial win for externally templated assignment operator.

x86 without tail call (current libc++)

0000000000000000 <std::string::operator=(std::string const&)>:
   0:   55                      push   %rbp
   1:   48 89 e5                mov    %rsp,%rbp
   4:   53                      push   %rbx
   5:   50                      push   %rax
   6:   48 89 fb                mov    %rdi,%rbx
   9:   48 39 f7                cmp    %rsi,%rdi
   c:   74 17                   je     25 <std::string::operator=(std::string const&)+0x25>
   e:   0f b6 56 17             movzbl 0x17(%rsi),%edx
  12:   84 d2                   test   %dl,%dl
  14:   79 07                   jns    1d <std::string::operator=(std::string const&)+0x1d>
  16:   48 8b 56 08             mov    0x8(%rsi),%rdx
  1a:   48 8b 36                mov    (%rsi),%rsi
  1d:   48 89 df                mov    %rbx,%rdi
  20:   e8 00 00 00 00          callq  25 <std::string::operator=(std::string const&)+0x25>
  25:   48 89 d8                mov    %rbx,%rax
  28:   48 83 c4 08             add    $0x8,%rsp
  2c:   5b                      pop    %rbx
  2d:   5d                      pop    %rbp
  2e:   c3                      retq

After:

0000000000000000 <std::string::operator=(std::string const&)>:
   0:   48 39 f7                cmp    %rsi,%rdi
   3:   74 14                   je     19 <std::string::operator=(std::string const&)+0x19>
   5:   0f b6 56 17             movzbl 0x17(%rsi),%edx
   9:   84 d2                   test   %dl,%dl
   b:   79 07                   jns    14 <std::string::operator=(std::string const&)+0x14>
   d:   48 8b 56 08             mov    0x8(%rsi),%rdx
  11:   48 8b 36                mov    (%rsi),%rsi
  14:   e9 00 00 00 00          jmpq   19 <std::string::operator=(std::string const&)+0x19>
  19:   48 89 f8                mov    %rdi,%rax
  1c:   c3                      retq

Benchmark (pending per https://reviews.llvm.org/D67667)

```
BM_StringAssignStr_Empty_Opaque                     6.23ns ± 0%             5.19ns ± 0%  -16.70%          (p=0.016 n=5+4)
BM_StringAssignStr_Empty_Transparent                5.86ns ± 0%             5.14ns ± 0%  -12.24%          (p=0.008 n=5+5)
BM_StringAssignStr_Small_Opaque                     8.79ns ± 1%             7.69ns ± 0%  -12.53%          (p=0.008 n=5+5)
BM_StringAssignStr_Small_Transparent                9.44ns ± 0%             8.00ns ± 0%  -15.26%          (p=0.008 n=5+5)
BM_StringAssignStr_Large_Opaque                     25.2ns ± 0%             24.3ns ± 0%   -3.50%          (p=0.008 n=5+5)
BM_StringAssignStr_Large_Transparent                23.6ns ± 0%             22.5ns ± 0%   -4.76%          (p=0.008 n=5+5)
BM_StringAssignStr_Huge_Opaque                       319ns ± 5%              317ns ± 5%     ~             (p=0.690 n=5+5)
BM_StringAssignStr_Huge_Transparent                  319ns ± 5%              317ns ± 5%     ~             (p=0.421 n=5+5)
BM_StringAssignAsciiz_Empty_Opaque                  7.41ns ± 0%             7.77ns ± 0%   +4.89%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Empty_Transparent             7.54ns ± 3%             7.30ns ± 0%   -3.24%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Small_Opaque                  9.87ns ± 0%            10.24ns ± 1%   +3.76%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Small_Transparent             10.4ns ± 1%              9.8ns ± 2%   -5.78%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Large_Opaque                  30.1ns ± 0%             30.1ns ± 0%     ~             (p=0.167 n=5+5)
BM_StringAssignAsciiz_Large_Transparent             27.1ns ± 0%             27.4ns ± 0%   +0.92%          (p=0.016 n=4+5)
BM_StringAssignAsciiz_Huge_Opaque                    383ns ± 4%              382ns ± 4%     ~             (p=0.548 n=5+5)
BM_StringAssignAsciiz_Huge_Transparent               375ns ± 0%              380ns ± 0%   +1.37%          (p=0.029 n=4+4)
BM_StringAssignAsciizMix_Opaque                     14.0ns ± 0%             14.0ns ± 0%     ~             (p=0.881 n=5+5)
BM_StringAssignAsciizMix_Transparent                13.7ns ± 1%             13.8ns ± 0%     ~             (p=0.056 n=5+5)
```

llvm-svn: 374137
2019-10-09 03:07:02 +00:00
Zoe Carver a9d43b55c7 [libc++] Remove C++03 variadics in shared_ptr (v2)
Summary: In my last patch (D67675) I forgot a few variadics. This patch removes the remaining make_shared and allocate_shared C++03 variadics.

    Reviewers: ldionne, EricWF, mclow.lists

    Subscribers: christof, dexonsmith, libcxx-commits

    Tags: #libc

    Differential Revision: https://reviews.llvm.org/D68000

llvm-svn: 373971
2019-10-07 21:41:15 +00:00
Louis Dionne 371ea70bb7 [libc++] Harden usage of static_assert against C++03
In C++03, we emulate static_assert with a macro, and we must parenthesize
multiple arguments.

llvm-svn: 373328
2019-10-01 12:12:21 +00:00
Eric Fiselier c8ad8686ac Refactor default constructor SFINAE in pair and tuple.
Refactor the  recent implicit default constructor changes to match the
existing SFINAE style.

llvm-svn: 373263
2019-09-30 20:55:30 +00:00
Louis Dionne 59e26308e6 [libc++] Take 2: Implement LWG 3158
Summary:
LWG 3158 marks the allocator_arg_t constructor of std::tuple as
conditionnally explicit based on whether the default constructors
of the tuple's members are explicitly default constructible.

This was previously committed as r372778 and reverted in r372832 due to
the commit breaking LLVM's build in C++14 mode. This issue has now been
addressed.

Reviewers: mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65232

llvm-svn: 373092
2019-09-27 15:06:52 +00:00
Louis Dionne e16f2cb678 [libc++] Take 2: Implement LWG 2510
Summary:
LWG2510 makes tag types like allocator_arg_t explicitly default
constructible instead of implicitly default constructible. It also
makes the constructors for std::pair and std::tuple conditionally
explicit based on the explicit-ness of the default constructibility
for the pair/tuple's elements.

This was previously committed as r372777 and reverted in r372832 due to
the commit breaking LLVM's build in C++14 mode. This issue has now been
addressed.

Reviewers: mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65161

llvm-svn: 372983
2019-09-26 14:51:10 +00:00
David Zarzycki a068601510 [libcxx] Do not implicitly #include assert.h
Users should only get the assert() macros if they explicitly include
them.

Found after switching from the GNU C++ stdlib to the LLVM C++ stdlib.

llvm-svn: 372963
2019-09-26 11:12:29 +00:00
Eric Fiselier af4a29af01 Add forward declaration of operator<< in <string_view> as required.
This declaration was previously missing despite appearing in the
synopsis. Users are still required to include <ostream> to get the
definition of the streaming operator.

llvm-svn: 372909
2019-09-25 18:56:54 +00:00
Marshall Clow e3f89a989a Add a missing default parameter to regex::assign. This is LWG3296; reviewed as https://reviews.llvm.org/D67944
llvm-svn: 372896
2019-09-25 16:40:30 +00:00
Ilya Biryukov a3d337a9a7 Revert r372777: [libc++] Implement LWG 2510 and its follow-ups
This also reverts:
 - r372778: [libc++] Implement LWG 3158
 - r372782: [libc++] Try fixing tests that fail on GCC 5 and older
 - r372787: Purge mentions of GCC 4 from the test suite

Reason: the change breaks compilation of LLVM with libc++, for details see
http://lists.llvm.org/pipermail/libcxx-dev/2019-September/000599.html

llvm-svn: 372832
2019-09-25 09:10:38 +00:00
Zoe Carver 4278a9e6b5 [libc++] Remove C++03 variadics in shared_ptr
Summary: As suggested by @ldionne in D66178, this patch removes C++03 variadics //only//. Following patches will apply more updates.

    Reviewers: ldionne, EricWF, mclow.lists

    Subscribers: christof, dexonsmith, libcxx-commits, ldionne

    Tags: #libc

    Differential Revision: https://reviews.llvm.org/D67675

llvm-svn: 372780
2019-09-24 20:55:54 +00:00
Louis Dionne e9e1c88ed9 [libc++] Implement LWG 3158
Summary:
LWG 3158 marks the allocator_arg_t constructor of std::tuple as
conditionnally explicit based on whether the default constructors
of the tuple's members are explicitly default constructible.

Reviewers: EricWF, mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65232

llvm-svn: 372778
2019-09-24 20:22:34 +00:00
Louis Dionne 95411dd426 [libc++] Implement LWG 2510
Summary:
LWG2510 makes tag types like allocator_arg_t explicitly default
constructible instead of implicitly default constructible. It also
makes the constructors for std::pair and std::tuple conditionally
explicit based on the explicit-ness of the default constructibility
for the pair/tuple's elements.

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65161

llvm-svn: 372777
2019-09-24 20:18:54 +00:00
Marshall Clow ab8f77a73e Revert "Extension: Mark the default constructor of chrono::duration as conditionally noexcept"; this breaks the gcc5 bot for C++11
This reverts commit c8ca15c95c4c0d6d1356500d5fe49a319ea4ca01.

llvm-svn: 372546
2019-09-23 06:16:41 +00:00
Marshall Clow d8ac51ab8f Extension: Mark the default constructor of chrono::duration as conditionally noexcept
llvm-svn: 372539
2019-09-23 04:16:48 +00:00
Dan Albert 85e26f56cb Revert "Revert "Implement std::condition_variable via pthread_cond_clockwait() where available""
With the fix for non-Linux.

This reverts commit c1c519d2f1.

llvm-svn: 372242
2019-09-18 18:13:32 +00:00
Dan Albert c1c519d2f1 Revert "Implement std::condition_variable via pthread_cond_clockwait() where available"
This reverts commit 5e37d7f9ff.

llvm-svn: 372034
2019-09-16 21:20:32 +00:00
Dan Albert a7e9059967 Open fstream files in O_CLOEXEC mode when possible.
Reviewers: EricWF, mclow.lists, ldionne

Reviewed By: ldionne

Subscribers: smeenai, dexonsmith, christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D59839

llvm-svn: 372027
2019-09-16 19:26:41 +00:00
Dan Albert 5e37d7f9ff Implement std::condition_variable via pthread_cond_clockwait() where available
std::condition_variable is currently implemented via
pthread_cond_timedwait() on systems that use pthread. This is
problematic, since that function waits by default on CLOCK_REALTIME
and libc++ does not provide any mechanism to change from this
default.

Due to this, regardless of if condition_variable::wait_until() is
called with a chrono::system_clock or chrono::steady_clock parameter,
condition_variable::wait_until() will wait using CLOCK_REALTIME. This
is not accurate to the C++ standard as calling
condition_variable::wait_until() with a chrono::steady_clock parameter
should use CLOCK_MONOTONIC.

This is particularly problematic because CLOCK_REALTIME is a bad
choice as it is subject to discontinuous time adjustments, that may
cause condition_variable::wait_until() to immediately timeout or wait
indefinitely.

This change fixes this issue with a new POSIX function,
pthread_cond_clockwait() proposed on
http://austingroupbugs.net/view.php?id=1216. The new function is
similar to pthread_cond_timedwait() with the addition of a clock
parameter that allows it to wait using either CLOCK_REALTIME or
CLOCK_MONOTONIC, thus allowing condition_variable::wait_until() to
wait using CLOCK_REALTIME for chrono::system_clock and CLOCK_MONOTONIC
for chrono::steady_clock.

pthread_cond_clockwait() is implemented in glibc (2.30 and later) and
Android's bionic (Android API version 30 and later).

This change additionally makes wait_for() and wait_until() with clocks
other than chrono::system_clock use CLOCK_MONOTONIC.<Paste>

llvm-svn: 372016
2019-09-16 17:57:48 +00:00
Eric Fiselier 6bc1236d39 Add debug check for null pointers passed to <string_view>
llvm-svn: 371925
2019-09-14 19:55:28 +00:00
Eric Fiselier cb9216b908 Fix C++03 build failures due to >>
llvm-svn: 371894
2019-09-13 20:30:45 +00:00
Eric Fiselier ffe8916cf2 Fix various test failures with GCC
llvm-svn: 371880
2019-09-13 18:40:46 +00:00
Eric Fiselier 2a573784f3 Recommit r370502: Make `vector` unconditionally move elements when
exceptions are disabled.

The patch was reverted due to some confusion about non-movable types. ie
types
that explicitly delete their move constructors. However, such types do
not meet
the requirement for `MoveConstructible`, which is required by
`std::vector`:

Summary:

`std::vector<T>` is free choose between using copy or move operations
when it
needs to resize. The standard only candidates that the correct exception
safety
guarantees are provided. When exceptions are disabled these guarantees
are
trivially satisfied. Meaning vector is free to optimize it's
implementation by
moving instead of copying.

This patch makes `std::vector` unconditionally move elements when
exceptions are
disabled. This optimization is conforming according to the current
standard wording.

There are concerns that moving in `-fno-noexceptions`mode will be a
surprise to
users. For example, a user may be surprised to find their code is slower
with
exceptions enabled than it is disabled. I'm sympathetic to this
surprised, but
I don't think it should block this optimization.

Reviewers: mclow.lists, ldionne, rsmith
Reviewed By: ldionne
Subscribers: zoecarver, christof, dexonsmith, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D62228

llvm-svn: 371867
2019-09-13 16:09:33 +00:00
Zoe Carver b51d5605b1 Consolidate swap, swap_ranges, and iter_swap in <type_traits>.
NFC. Thanks to @Quuxplusone (Arthur O'Dwyer) for this change.

llvm-svn: 371639
2019-09-11 17:39:24 +00:00
Dimitry Andric 5bd4a4806a Remove ::gets for FreeBSD 13 and later
Summary:
In https://svnweb.freebsd.org/changeset/base/351659 @emaste removed gets() from
FreeBSD 13's libc, and our copies of libc++ and libstdc++.  In that change, the
declarations were simply deleted, but I would like to propose this conditional
test instead.

Reviewers: EricWF, mclow.lists, emaste

Reviewed By: mclow.lists

Subscribers: krytarowski, christof, ldionne, emaste, libcxx-commits

Differential Revision: https://reviews.llvm.org/D67316

llvm-svn: 371324
2019-09-07 22:18:20 +00:00
Louis Dionne b370e7691a [libc++] Revert "Make `vector` unconditionally move elements when exceptions are disabled."
This reverts r370502, which broke the use case of a copy-only T (with a
deleted move constructor) when exceptions are disabled. Until we figure
out the right behavior, I'm reverting the commit.

llvm-svn: 371068
2019-09-05 13:50:28 +00:00
Louis Dionne b92deded87 [libc++] Move __clamp_to_integral to <cmath>, and harden against min()/max() macros
llvm-svn: 370900
2019-09-04 13:35:03 +00:00
Louis Dionne e8316372b9 [libc++] Add `__truncating_cast` for safely casting float types to integers
This is needed anytime we need to clamp an arbitrary floating point
value to an integer type.

Thanks to Eric Fiselier for the patch.

Differential Revision: https://reviews.llvm.org/D66836

llvm-svn: 370891
2019-09-04 12:48:32 +00:00
Louis Dionne 801f6a495c [libc++] Use __extension__ in a portable manner
llvm-svn: 370889
2019-09-04 12:44:19 +00:00
Louis Dionne 79b476150b [libc++] Mark usage of _Atomic with __extension__
An upcoming change in Clang will flag _Atomic as being a C11 extension.
To avoid generating this warning in libc++, this commit marks the only
use of _Atomic with the __extension__ extension, which suppresses such
warnings.

llvm-svn: 370796
2019-09-03 17:52:18 +00:00
Eric Fiselier 2dd37a31ce Make `vector` unconditionally move elements when exceptions are disabled.
Summary:
`std::vector<T>` is free choose between using copy or move operations when it needs to resize. The standard only candidates that the correct exception safety guarantees are provided. When exceptions are disabled these guarantees are trivially satisfied. Meaning vector is free to optimize it's implementation by moving instead of copying.

This patch makes `std::vector` unconditionally move elements when exceptions are disabled.

This optimization is conforming according to the current standard wording.

There are concerns that moving in `-fno-noexceptions`mode will be a surprise to users. For example, a user may be surprised to find their code is slower with exceptions enabled than it is disabled. I'm sympathetic to this surprised, but I don't think it should block this optimization.


Reviewers: mclow.lists, ldionne, rsmith

Reviewed By: ldionne

Subscribers: zoecarver, christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D62228

llvm-svn: 370502
2019-08-30 19:01:03 +00:00
Louis Dionne f7a544bca8 [libc++] Fix visibility of __vector_base_common on GCC
Since we build the library with -fvisibility=hidden, the shared object
wouldn't contain __vector_base_common<true>::__throw_length_error()
and __vector_base_common<true>::__throw_out_of_range(), leading to
link errors. This only happened on GCC for some reason.

https://llvm.org/PR43140

llvm-svn: 370240
2019-08-28 18:10:39 +00:00
David Spickett e2b200b7bf [libcxx] Only declare contents of threading API when
_LIBCPP_HAS_THREAD_API_EXTERNAL is not defined.

When it is defined they will be declared by the
__external_threading header instead.

Differential revision: https://reviews.llvm.org/D66518

llvm-svn: 369537
2019-08-21 15:38:24 +00:00
Marshall Clow 4f41779cca Add a missing _VSTD:: before a call to merge. Fixes PR43034. Checked the rest of 'algorithm' looking for unqualified calls. Didn't find any.
llvm-svn: 369463
2019-08-20 22:23:35 +00:00
Marshall Clow 7fa6865392 Fix a couple of unguarded operator, calls in algorithm. Fixes PR#43063. Updated all the heap tests to check this.
llvm-svn: 369448
2019-08-20 21:31:51 +00:00
Louis Dionne fc4486c247 [libc++] Implement LWG 3199
Summary:
The resolution of LWG 3199 makes sure that input-streaming into an empty bitset
does not set the failbit on the input stream.

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65105

llvm-svn: 369422
2019-08-20 18:21:06 +00:00
Marshall Clow 696630eaf2 Fix availability of __thread_id on builds with external threading. Reviewed as https://reviews.llvm.org/D66480
llvm-svn: 369399
2019-08-20 16:16:23 +00:00
Louis Dionne a47ca1ea6d [libc++] Explicitly cast in generate_canonical
A new clang warning introduced in r367497 was complaining about
the change in value.

Thanks to Brian Cain for the patch.
Differential Revision: https://reviews.llvm.org/D66422

llvm-svn: 369393
2019-08-20 15:39:20 +00:00
Mikhail Maltsev a83220c6f2 [libcxx] Fix build breakage on mips
Fixes https://bugs.llvm.org/show_bug.cgi?id=43011 caused by
https://reviews.llvm.org/D63284.

Committing as obvious.

llvm-svn: 369364
2019-08-20 10:19:55 +00:00
Zoe Carver 471bbb6e72 [libc++] reverts commit a5f5aad568.
The commit being reverted caused segfaults when building
with libc++ and GCC (and possibly other configurations).

Differential Revision: https://reviews.llvm.org/D62868

llvm-svn: 369270
2019-08-19 15:47:16 +00:00
Marshall Clow 2e80d01fa7 Fix thread comparison by making sure we never pass our special 'not a thread' value to the underlying implementation. Fixes PR#42918.
llvm-svn: 368916
2019-08-14 20:54:56 +00:00
Zoe Carver a5f5aad568 This commit removes std::shared_ptr::make_shared and std::shared_ptr::allocate_shared as they are not part of the standard. This commit also adds the helper function "__create_with_cntrl_block" which std::allocate_shared and std::make_shared have been updated to use.
llvm-svn: 368885
2019-08-14 17:19:25 +00:00
Louis Dionne 619172a818 [libc++] Enable <chrono> ""d and ""y literals for AppleClang 10 and up
AppleClang supports those literals starting in version 10.0.1.

llvm-svn: 368882
2019-08-14 17:04:31 +00:00
Louis Dionne 3555af7120 [libc++] Do not define _LIBCPP_CLANG_VER for non-LLVM Clang
In r292833, we started defining _LIBCPP_CLANG_VER to 0 for Apple Clang.
The result is that AppleClang is detected as being a very old version
of LLVM Clang (version 0), which is obviously incorrect.

I believe this was added so that we don't have to check whether
_LIBCPP_CLANG_VER is defined prior to comparing it with a number
(which can trigger a warning). This commit also fixes the two
places that use the macro correspondingly.

llvm-svn: 368880
2019-08-14 17:01:08 +00:00
Marshall Clow 2b1d42541f Rework recursive_timed_mutex so that it uses __thread_id instead of using the lower-level __libcpp_thread_id. This is prep for fixing PR42918. Reviewed as https://reviews.llvm.org/D65895
llvm-svn: 368867
2019-08-14 16:21:27 +00:00
Louis Dionne 8a033a9e3f [libc++] Always build with -fvisibility=hidden
Summary:
This avoids symbols being accidentally exported from the dylib when they
shouldn't. The next step is to use a pragma to apply hidden visibility
to all declarations (unless otherwise specified), which will allow us
to drop the per-declaration hidden visibility attributes we currently
have.

This also has the nice side effect of making sure the dylib exports the
same symbols regardless of the optimization level.

PR38138

Reviewers: EricWF, mclow.lists

Subscribers: mgorny, christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D62868

llvm-svn: 368703
2019-08-13 15:02:53 +00:00
Louis Dionne 86dd28a547 [libc++] Use [[nodiscard]] for lock_guard, as an extension
Summary:
D64914 added support for applying [[nodiscard]] to constructors. This
commit uses that capability to flag incorrect uses of std::lock_guard
where one forgets to actually create a variable for the lock_guard.

rdar://45790820

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits, Quuxplusone, lebedev.ri

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65900

llvm-svn: 368664
2019-08-13 11:12:28 +00:00
Louis Dionne 1308011e1b [libc++] Implement CTAD for std::tuple
Summary:
We were using implicit deduction guides instead of explicit ones,
however the implicit ones don't do work anymore when changing the
constructors.

This commit adds the actual guides specified in the Standard to make
libc++ (1) closer to the Standard and (2) more resistent to changes
in std::tuple's constructors.

Reviewers: Quuxplusone

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65225

llvm-svn: 368599
2019-08-12 18:30:31 +00:00
Eric Fiselier b0945e1bd2 Improve codegen for deque.
This patch rewrites a few loops in deque and split_buffer to better
optimize the codegen. For constructors like
`deque<unsigned char> d(500000, 0);` this patch results in a 2x speedup.

The patch improves the codegen  in roughly three ways:

1. Changes do { ... } while (...) loops into more typical for loops.
  The optimizer can reason about normal looking loops better.

2. Split the iteration over a range into (A) iteration over the blocks,
then (B) iteration within the block. This nested structure helps LLVM
lower the inner loop to `memset`.

3. Do fewer things each iteration. Some of these loops were incrementing
  or changing 4-5 variables every loop (in addition to the
  construction). Previously most loops would increment the end pointer,
  the size, and decrement the count of remaining items to construct.
  Now we only increment a single pointer for most iterations.

llvm-svn: 368547
2019-08-12 07:51:05 +00:00
Marshall Clow fde236b1f7 Implement hh_mm_ss from P1466R3. Reviewed as https://reviews.llvm.org/D65365.
llvm-svn: 368299
2019-08-08 14:36:07 +00:00
Louis Dionne 956892433f [pstl][libc++] Provide uglified header names for interface headers
For the few (currently four) headers that make up the PSTL's interface
to other Standard Libraries, provide a stable uglified header file that
can be included by those Standard Libraries.

We can then more easily change the internal organization of the PSTL
without having to change the integration with Standard Libraries.

llvm-svn: 368088
2019-08-06 21:11:24 +00:00
Louis Dionne 0a06eb911b [libc++] Take 2: Integrate the PSTL into libc++
Summary:
This commit allows specifying LIBCXX_ENABLE_PARALLEL_ALGORITHMS when
configuring libc++ in CMake. When that option is enabled, libc++ will
assume that the PSTL can be found somewhere on the CMake module path,
and it will provide the C++17 parallel algorithms based on the PSTL
(that is assumed to be available).

The commit also adds support for running the PSTL tests as part of
the libc++ test suite.

The first attempt to commit this failed because it exposed a bug in the
tests for modules. Now that this has been fixed, it should be safe to
commit this.

Reviewers: EricWF

Subscribers: mgorny, christof, jkorous, dexonsmith, libcxx-commits, mclow.lists, EricWF

Tags: #libc

Differential Revision: https://reviews.llvm.org/D60480

llvm-svn: 367903
2019-08-05 18:29:14 +00:00
Eric Fiselier 278d593014 Revert "Suppress -Wctad-maybe-unsupported on types w/o deduction guides."
Some modules builds are issuing buggy diagnostics. The cause of which is
TBD.

This reverts commit r@367770.

llvm-svn: 367777
2019-08-04 07:13:43 +00:00
Eric Fiselier fcd549a7d8 Suppress -Wctad-maybe-unsupported on types w/o deduction guides.
There are a handful of standard library types that are intended
to support CTAD but don't need any explicit deduction guides to
do so.

This patch adds a dummy deduction guide to those types to suppress
-Wctad-maybe-unsupported (which gets emitted in user code).

llvm-svn: 367770
2019-08-03 23:54:29 +00:00
Eric Fiselier 208e8a1b66 Revert accidental change to __member_pointer_traits_imp.
A previous patch accidentally made the primary template
an incomplete type. This broke some C++03 constructs.

llvm-svn: 367762
2019-08-03 19:03:22 +00:00
Eric Fiselier 10bf563171 Simplify <type_traits> implementations.
This patch rewrites a number of old meta-function implementations
that assumed const/volatile could not be safely applied to all types.
This is no longer the case, though for some types (Ex function types),
the const qualifier can be ignored.

The largest improvement in this patch is the reduction of is_function.
Thanks to Matt Calabrese for the improved implementation.

llvm-svn: 367749
2019-08-03 05:01:34 +00:00
Eric Fiselier d544d1441d Refactor deque to centralize handling of spare blocks.
I have upcoming changes that modify how deque handles spare blocks.
This cleanup is intended to make those changes easier to review
and understand. This patch should have NFC.

llvm-svn: 367631
2019-08-01 23:11:18 +00:00
Eric Fiselier 3eb5aec61f Change default bucket count in hash_set/hash_map.
Previously these types rehashed to a table of 193 elements
upon construction. But this is non-ideal, first because default
constructors should not allocate unless necessary, and second
because 193 is big and can waste a bunch of memory.

This number had previously been chosen to match GCC's implementation.

llvm-svn: 367605
2019-08-01 19:48:29 +00:00
Nico Weber 9aae539d4c libcxx: Define __STDCPP_THREADS__ to 1, not to __cplusplus.
[cpp.predefined]p2:

   __STDCPP_THREADS__
    Defined, and has the value integer literal 1, if and only if a program
    can have more than one thread of execution .

Also define it only if it's not defined already, since it's supposed
to be defined by the compiler.

Also move it from thread to __config (which requires setting it only
if _LIBCPP_HAS_NO_THREADS is not defined).

Part of PR33230. The intent is to eventually make the compiler define
this instead.

llvm-svn: 367316
2019-07-30 14:32:47 +00:00
Eric Fiselier d4ace50ed0 Fix PR35637: suboptimal codegen for `vector<unsigned char>`.
The optimizer is petulant and temperamental. In this case LLVM failed to lower
the the "insert at end" loop used by`vector<unsigned char>` to a `memset` despite
`memset` being substantially faster over a range of bytes.

LLVM has the ability to lower loops to `memset` whet appropriate, but the
odd nature of libc++'s loops prevented the optimization from taking places.

This patch addresses the issue by rewriting the loops from the form
`do [ ... --__n; } while (__n > 0);` to instead use a for loop over a pointer
range (For example: `for (auto *__i = ...; __i < __e; ++__i)`).

This patch also rewrites the asan annotations to unposion all additional memory
at the start of the loop instead of once per iterations. This could potentially
permit false negatives where the constructor of element N attempts to access
element N + 1 during its construction.

The before and after results for the `BM_ConstructSize/vector_byte/5140480_mean`
benchmark (run 5 times) are:

--------------------------------------------------------------------------------------------
Benchmark                                                 Time             CPU   Iterations
--------------------------------------------------------------------------------------------
Before
------
BM_ConstructSize/vector_byte/5140480_mean          12530140 ns     12469693 ns            N/A
BM_ConstructSize/vector_byte/5140480_median        12512818 ns     12445571 ns            N/A
BM_ConstructSize/vector_byte/5140480_stddev          106224 ns       107907 ns            5
-----
After
-----
BM_ConstructSize/vector_byte/5140480_mean            167285 ns       166500 ns            N/A
BM_ConstructSize/vector_byte/5140480_median          166749 ns       166069 ns            N/A
BM_ConstructSize/vector_byte/5140480_stddev            3242 ns         3184 ns            5

llvm-svn: 367183
2019-07-28 04:37:02 +00:00
Marshall Clow 736e8aa8ed Fix a bug in std::chrono::abs where it would fail when the duration's period had not been reduced.s
llvm-svn: 367120
2019-07-26 15:10:46 +00:00
Louis Dionne 568bb7eeb6 [NFC][libcxx] Add comments about making mutex/condition_variable trivial on Apple platforms
Leaving some comments behind so that we avoid re-having that discussion
in the future.

llvm-svn: 367048
2019-07-25 20:29:20 +00:00
Marshall Clow db99d3a2a2 Implement change #4 of P1466: Change weekday to accept both 0 and 7 as Sunday. Add accessors 'c_encoding' and 'iso_encoding' to provide different interpretations of the weekday. Remove 'operator unsigned'
llvm-svn: 366981
2019-07-25 03:26:05 +00:00
Marshall Clow 30f12a4247 Implement most of P1612R1: Relocate endian. Moves the std::endian functionality from 'type-traits' to 'bit'. No other change. The reason that this is 'partial' is that P1621 also recommends a feature-test macro, but I don't have the value for that one yet. In a month or so, I'll add that
llvm-svn: 366776
2019-07-23 04:20:19 +00:00
Louis Dionne e35c5121da [NFC][libc++] Add missing EXPLICIT to pair and tuple synopsis
The constructors for std::pair and std::tuple have been made conditionally
explicit, however the synopsis in the headers do not reflect that.

llvm-svn: 366735
2019-07-22 20:45:23 +00:00
Petr Hosek 89385633ba [libc++] Set __file_ to 0 in basic_filebuf::close() even if fclose fails
This issue was detected by ASan in one of our tests. This test manually
invokes basic_filebuf::cloe(). fclose(__h.release() returned a non-zero
exit status, so __file_ wasn't set to 0. Later when basic_filebuf
destructor ran, we would enter the if (__file_) block again leading to
heap-use-after-free error.

The POSIX specification for fclose says that independently of the return
value, fclose closes the underlying file descriptor and any further
access (including another call to fclose()) to the stream results in
undefined behavior. This is exactly what happened in our test case.

To avoid this issue, we have to always set __file_ to 0 independently of
the fclose return value.

Differential Revision: https://reviews.llvm.org/D64979

llvm-svn: 366730
2019-07-22 19:54:34 +00:00
Louis Dionne a3c83b7511 Revert "[libc++] Integrate the PSTL into libc++"
This reverts r366593, which caused unforeseen breakage on the build bots.
I'm reverting until the problems have been figured out and fixed.

llvm-svn: 366603
2019-07-19 18:52:46 +00:00
Louis Dionne a5bd48939c [libc++] Use _EnableIf instead of std::enable_if in deduction guides for map and set
llvm-svn: 366594
2019-07-19 17:13:39 +00:00
Louis Dionne 910323e667 [libc++] Integrate the PSTL into libc++
Summary:
This commit allows specifying LIBCXX_ENABLE_PARALLEL_ALGORITHMS when
configuring libc++ in CMake. When that option is enabled, libc++ will
assume that the PSTL can be found somewhere on the CMake module path,
and it will provide the C++17 parallel algorithms based on the PSTL
(that is assumed to be available).

The commit also adds support for running the PSTL tests as part of
the libc++ test suite.

Reviewers: rodgert, EricWF

Subscribers: mgorny, christof, jkorous, dexonsmith, libcxx-commits, mclow.lists, EricWF

Tags: #libc

Differential Revision: https://reviews.llvm.org/D60480

llvm-svn: 366593
2019-07-19 17:02:42 +00:00
Louis Dionne e068c7463f [libc++] Fix link error with _LIBCPP_HIDE_FROM_ABI_PER_TU and std::string
Summary:
This is effectively a revert of r344616, which was a partial fix for
PR38964 (compilation of <string> with GCC in C++03 mode). However, that
configuration is explicitly not supported anymore and that partial fix
breaks compilation with Clang when per-TU insulation is provided.

PR42676
rdar://52899715

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D64941

llvm-svn: 366567
2019-07-19 11:52:55 +00:00
Louis Dionne e1eabcdfad [libc++] Add C++17 deduction guides for std::function
Summary: http://llvm.org/PR39606

Reviewers: Quuxplusone

Subscribers: christof, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54410

llvm-svn: 366484
2019-07-18 19:50:56 +00:00
Hans Wennborg 8f5b44aead Bump the trunk version to 10.0.0svn
and clear the release notes.

llvm-svn: 366427
2019-07-18 11:51:05 +00:00
Zoe Carver a17b1aed6a Add contains method to associative containers. This patch implements P0458R2, adding contains to map, multimap, unordered_map, unordered_multimap, set, multiset, unordered_set, and unordered_multiset.
llvm-svn: 366170
2019-07-16 03:21:01 +00:00
Louis Dionne dfcd4384cb [libc++] Implement P0433: deduction guides for <unordered_map>
Thanks to Arthur O'Dwyer for the patch.

Differential Revision: https://reviews.llvm.org/D58590

llvm-svn: 366124
2019-07-15 20:06:01 +00:00
Eric Fiselier 4066978cb7 Improve compile time of variant.
In particular, improve the compile time of the overload set builder
that variant uses to determine which alternative to construct.

Instead of having the __overload type construct itself recursively,
this patch uses a flat construction for the overload set.

llvm-svn: 366033
2019-07-14 21:29:39 +00:00
Eric Fiselier aae0cb67ed Cleanup whitespace in <variant>. NFC.
llvm-svn: 366026
2019-07-14 18:31:55 +00:00
Eric Fiselier 194b337f33 Avoid eager template instantiation caused by the variant narrowing checks.
The standard disallows narrowing conversions when constructing a variant.
This is checked by attempting to perform braced initialization of the
destination type from the argument type. However, braced initialization
can force the compiler (mostly clang) to eagerly instantiate the
constructors of the destintation type -- which can lead to errors in
a non-immediate context.

However, as variant is currently specified, the narrowing checks only
observably apply when the destination type is arithmetic. Meaning we can
skip the check for class types. Hense avoiding the hard errors.

In order to cause fewer build breakages, this patch avoids the narrowing
check except when the destination type is arithmetic.

llvm-svn: 366022
2019-07-14 18:21:15 +00:00
Eric Fiselier 882fdf68b7 Fix non-conformance it `std::tuple`.
Previously we implemented all one trillion tuple-like constructors using
a single generic overload. This worked fairly well, except that it
differed in behavior from the standard version because it didn't
consider both T&& and T const&. This was observable for certain
types.

This patch addresses that issue by splitting the generic constructor
in two. We now provide both T&& and T const& versions of the
tuple-like constructors (sort of).

llvm-svn: 365973
2019-07-12 23:01:48 +00:00
Eric Fiselier 128af31595 Add option to disable variant narrowing conversion changes.
The paper P0608R3 - "A sane variant converting constructor" disallows
narrowing conversions in variant. It was meant to address this
surprising problem:

  std::variant<std::string, bool> v = "abc";
  assert(v.index() == 1); // constructs a bool.

However, it also disables every potentially narrowing conversion. For
example:

  variant<unsigned> v = 0; // ill-formed
  variant<string, double> v2 = 42; // ill-formed (int -> double narrows)

These latter changes break code. A lot of code. Within Google it broke
on the order of a hundred thousand target with thousands of root causes
responsible for the breakages.

Of the breakages related to the narrowing restrictions, none of them
exposed outstanding bugs. However, the breakages caused by boolean
conversions (~13 root causes), all but one of them were bugs.

For this reasons, I am adding a flag to disable the narrowing conversion
changes but not the boolean conversions one.

One purpose of this flag is to allow users to opt-out of breaking changes
in variant until the offending code can be cleaned up. For non-trivial
variant usages the amount of cleanup may be significant.

This flag is also required to support automated tooling, such as
clang-tidy, that can automatically fix code broken by this change.
In order for clang-tidy to know the correct alternative to construct,
it must know what alternative was being constructed previously, which
means running it over the old version of std::variant.

Because this change breaks so much code, I will be implementing the
aforementioned clang-tidy check in the very near future.

Additionally I'm plan present this new information to the committee so they can
re-consider if this is a breaking change we want to make.

I think libc++ should very seriously consider pulling this change
before the 9.0 release branch is cut. But that's a separate discussion
that I will start on the lists.

For now this is the minimal first step.

llvm-svn: 365960
2019-07-12 21:32:11 +00:00
Marshall Clow f3b851f0b8 Reorganize the 'bit' header to make most of the facilities available for internal use pre-C++20. NFC for external users
llvm-svn: 365854
2019-07-12 01:01:55 +00:00
Eric Fiselier 41798c05cd Fix memory leak in set and map.
When assigning an initializer list into set/map, libc++ would
leak memory if the initializer list contained equivalent keys
because we failed to check if the insertion was successful.

llvm-svn: 365840
2019-07-11 23:13:38 +00:00
Louis Dionne 296a80102a [libc++] Implement deduction guides for <unordered_set>
Thanks to Arthur O'Dwyer for the patch.
Differential Revision: https://reviews.llvm.org/D58617

llvm-svn: 365788
2019-07-11 15:16:39 +00:00
Marshall Clow f814dcbafb Make forward_list::remove/remove_if/unique all return void before C++20; undoes that bit of D58332. Thanks to Mikhail Maltsev for pointing this out
llvm-svn: 365290
2019-07-08 03:45:28 +00:00
Eric Fiselier 8cedf04a6c Make ~mutex and ~condition_variable trivial on Windows.
The implementations of __libcpp_mutex_destroy and __libcpp_condvar_destroy
are already NOPs, so this optimization is safe to perform.

See r365273 and PR27658 for more information.

llvm-svn: 365281
2019-07-07 17:24:03 +00:00
Eric Fiselier 8baf83839e Fix PR27658 - Make ~mutex trivial when possible.
Currently std::mutex has a constexpr constructor, but a non-trivial
destruction.

The constexpr constructor is required to ensure the construction of a
mutex with static storage duration happens at compile time, during
constant initialization, and not during dynamic initialization.
This means that static mutex's are always initialized and can be used
safely during dynamic initialization without the "static initialization
order fiasco".

A trivial destructor is important for similar reasons. If a mutex is
used during dynamic initialization it might also be used during program
termination. If a static mutex has a non-trivial destructor it will be
invoked during termination. This can introduce the "static
deinitialization order fiasco".

Additionally, function-local statics emit a guard variable around
non-trivially destructible types. This results in horrible codegen and
adds a runtime cost to every call to that function. non-local static's
also result in slightly worse codegen but it's not as big of a problem.

Example codegen can be found here: https://goo.gl/3CSzbM

Note: This optimization is not safe with every pthread implementation.
Some implementations allocate on the first call to pthread_mutex_lock
and free the allocation in pthread_mutex_destroy.

Also, changing the triviality of the destructor is not an ABI break.
At least to the best of my knowledge :-)

llvm-svn: 365273
2019-07-07 01:20:54 +00:00
Marshall Clow 1ab3fe8a7a Make list::remove/remove_if/unique all return void before C++20; undoes that bit of D58332. Thanks to Mikhail Maltsev for pointing this out
llvm-svn: 365261
2019-07-06 06:10:03 +00:00
Zoe Carver 28e0187175 This patch makes swap functions constexpr. Both swap overloads, swap_ranges and iter_swap are updated (with tests).
llvm-svn: 365238
2019-07-05 20:13:34 +00:00
Eric Fiselier f1807a7df6 Fix tuple's conditionally explicit constructors for very weird user
types.

It seems some people like to write types that can explicitly convert
to anything, but cannot be used to explicitly construct anything.

This patch makes tuple tolerate such types, as is required
by the standard.

llvm-svn: 365074
2019-07-03 19:21:40 +00:00
Louis Dionne 1c478d6e85 [libc++] Update availability markup for Filesystem on Apple platforms
llvm-svn: 365068
2019-07-03 18:29:02 +00:00
Marshall Clow bd7f84a482 Use new '__libcpp_is_constant_evaluated' call to remove an '#ifdef' from the bit code. NFC
llvm-svn: 364884
2019-07-02 03:21:16 +00:00
Marshall Clow 745379a0af Mark the newly added '__libcpp_is_constant_evaluated' as 'inline', since it can be included multiple times by multiple headers, and we don't want 'duplicate definition' errors.
llvm-svn: 364879
2019-07-02 00:20:06 +00:00
Marshall Clow 491ddc00ae Add a private call '__libcpp_is_constant_evaluated' which 'works' for old language versions and w/o any compiler support. 'Working', in this case, means that it returns false in those cases.
llvm-svn: 364873
2019-07-01 23:16:46 +00:00
Marshall Clow a5c3485a58 Bit Operations: P0556, P0553 and P1355. Reviewed as: https://reviews.llvm.org/D51262
llvm-svn: 364862
2019-07-01 23:00:32 +00:00
Eric Fiselier d1523f7a8c Ensure bitset's string constructor doesn't poison the overload set.
llvm-svn: 364842
2019-07-01 19:59:34 +00:00
Marshall Clow 24edf8ef4b Implement P0646R1: Erase-Like Algorithms Should Return size_type. Reviewed as https://reviews.llvm.org/D58332, and then updated because I rewrote a couple of those routines to eliminate some UB. Thanks to Zoe for tghe patch.
llvm-svn: 364840
2019-07-01 19:22:00 +00:00
Marshall Clow 3c125fe821 Implement LWG2221: 'Formatted output for nullptr_t' Reviewed as: https://reviews.llvm.org/D63053
llvm-svn: 364802
2019-07-01 16:20:25 +00:00
Bruce Mitchener 4603460a39 __threading_support: Remove (void) in favor of ().
Summary:
This fixes a clang-tidy warning when building something that uses
this file.

Reviewers: mclow.lists, EricWF

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D43226

llvm-svn: 364799
2019-07-01 16:18:38 +00:00
Bruce Mitchener ba41d3b1fd Fix -Wdouble-promotion warnings.
Reviewers: mclow.lists

Subscribers: christof, ldionne, cfe-commits, libcxx-commits

Differential Revision: https://reviews.llvm.org/D62782

llvm-svn: 364798
2019-07-01 16:13:31 +00:00
Marshall Clow 954014a0fa Add a missing '__uncvref_t' to the SFINAE constraints for optional's assignment operator. Fixes PR38638. Thanks to Jonathan Wakely for the report
llvm-svn: 364574
2019-06-27 18:40:55 +00:00
Marshall Clow 9318430237 Provide hashers for string_view only if they are using the default char_traits. Seen on SO: test/std/strings/string.view/string.view.hash/char_type.hash.fail.cpp
llvm-svn: 364545
2019-06-27 14:18:32 +00:00
Eric Fiselier ae9e42f614 Revert "Change the ABI version and ABI namespace to be `_LIBCPP_VERSION`"
There are some suspicious bot failures that I want to ensure aren't
caused by this patch.

I'll recommit tomorrow.

llvm-svn: 364363
2019-06-26 00:05:14 +00:00
Eric Fiselier 1fa0f4b942 Change the ABI version and ABI namespace to be `_LIBCPP_VERSION`
when _LIBCPP_ABI_UNSTABLE is defined.

User defined _LIBCPP_ABI_NAMESPACE will still be respected,
but the default version namespace in unstable mode will be the libc++ version
(Currently '__9000').

Previously  `_LIBCPP_ABI_VERSION` and `_LIBCPP_ABI_NAMESPACE` were
`1` and `__1` respectively, whuch conflicted with the stable ABI

llvm-svn: 364354
2019-06-25 22:13:39 +00:00
Eric Fiselier fb2bd4a939 Use C++11 implementation of unique_ptr in C++03.
llvm-svn: 364161
2019-06-23 20:47:21 +00:00
Eric Fiselier 3359a17b3a Apply new meta-programming traits throughout the library.
The new meta-programming primitives are lower cost than the old versions. This patch removes those old versions and switches libc++ to use the new ones.

llvm-svn: 364160
2019-06-23 20:28:29 +00:00
Eric Fiselier de2b633a4a Add super fast _IsSame trait for internal use.
Clang provides __is_same that doesn't produce any instantiations
and just returns a bool. It's a lot faster than using std::is_same

I'll follow up with a patch to actually start using it.

llvm-svn: 364148
2019-06-23 03:58:41 +00:00
Eric Fiselier cf92a1f6eb Add noexcept throughout <atomic>
The CMake CheckLibcxxAtomic module was always failing to compile
the example, even when libatomic wasn't needed. This was caused
because the check doesn't link a C++ runtime library to provide
std::terminate, which is required for exception support.

The check is still really broken, but <atomic> is better!

llvm-svn: 364146
2019-06-23 02:49:12 +00:00
Eric Fiselier 51a741c87f Add new style meta-programming primatives.
Using class templates instead of alias templates causes a lot of
instantiations. As part of the move away from C++03, we want to
improve the efficiency of our meta-programming.

This patch lays the groundwork by introducing new _If, _EnableIf,
_And, _Or, and _IsValidExpansion (detect member). Future patches
will replace the existing implementations after verifying there
compile time differences.

llvm-svn: 364114
2019-06-21 23:37:52 +00:00
Marshall Clow 410b650e67 Implement P0340R3: Make 'underlying_type' SFINAE-friendly. Reviewed as https://reviews.llvm.org/D63574
llvm-svn: 364094
2019-06-21 18:57:06 +00:00
Eric Fiselier e652f8097b Use rvalue references throughout the is_constructible traits.
llvm-svn: 364065
2019-06-21 15:35:33 +00:00
Eric Fiselier 000f25a37e Make move and forward work in C++03.
These functions are key to allowing the use of rvalues and variadics
in C++03 mode. Everything works the same as in C++11, except for one
tangentially related case:

struct T {
  T(T &&) = default;
};

In C++11, T has a deleted copy constructor. But in C++03 Clang gives
it both a move and a copy constructor. This seems reasonable enough
given the extensions it's using.

The other changes in this patch were the minimal set required
to keep the tests passing after the move/forward change. Most notably
the removal of the `__rv<unique_ptr>` hack that was present
in an attempt to make unique_ptr move only without language support.

llvm-svn: 364063
2019-06-21 15:20:55 +00:00
Eric Fiselier f044ebeb8d Enable aligned_union in C++03
llvm-svn: 364058
2019-06-21 14:45:08 +00:00
Eric Fiselier 3503d84ae0 Remove dead non-variadic workarounds in <type_traits>
We can use variadics with clang

llvm-svn: 364054
2019-06-21 14:37:28 +00:00
Eric Fiselier 87cf92d9cb Make rvalue metaprogramming traits work in C++03.
The next step is to get move and forward working in C++03.

llvm-svn: 364053
2019-06-21 14:31:34 +00:00
Eric Fiselier 5b4cc84b87 Remove even more dead code.
llvm-svn: 364050
2019-06-21 14:09:32 +00:00
Eric Fiselier 395c7330e4 Assume __is_final, __is_base_of, and friends.
All the compilers we support provide these builtins. We don't
need to do a configuration dance anymore.

This patch also cleans up some dead or almost dead
C++11 feature detection macros.

llvm-svn: 364047
2019-06-21 13:56:13 +00:00
Eric Fiselier 8d30a6e40c Remove dead config now that C++03 requires Clang.
llvm-svn: 364031
2019-06-21 11:32:43 +00:00
Mikhail Maltsev cfdc7f0d7e [libc++] Avoid using timespec when it might not be available
Summary:
The type timespec is unconditionally used in __threading_support.
Since the C library is only required to provide it in C11, this might
cause problems for platforms with external thread porting layer (i.e.
when _LIBCPP_HAS_THREAD_API_EXTERNAL is defined) with pre-C11
C libraries.

In our downstream port of libc++ we used to provide a definition of
timespec in __external_threading, but this solution is not ideal
because timespec is not a reserved name.

This patch renames timespec into __libcpp_timespec_t in the
thread-related parts of libc++. For all cases except external
threading this type is an alias for ::timespec (and no functional
changes are intended).

In case of external threading it is expected that the
__external_threading header will either provide a similar typedef (if
timespec is available in the vendor's C library) or provide a
definition of __libcpp_timespec_t compatible with POSIX timespec.

Reviewers: ldionne, mclow.lists, EricWF

Reviewed By: ldionne

Subscribers: dexonsmith, libcxx-commits, christof, carwil

Tags: #libc

Differential Revision: https://reviews.llvm.org/D63328

llvm-svn: 364012
2019-06-21 08:33:47 +00:00
Zhihao Yuan 4513f0f022 [libc++] Recommit r363692 to implement P0608R3
Re-apply the change which was reverted in r363764 as-is after
breakages being resolved.  Thanks Eric Fiselier for working
hard on this.

See also: https://bugs.llvm.org/show_bug.cgi?id=42330

Differential Revision: https://reviews.llvm.org/D44865

llvm-svn: 363993
2019-06-20 22:09:40 +00:00
Louis Dionne f2f7d72f00 [libc++] Take 2: Implement CTAD for map and multimap
This is a re-application of r362986 (which was reverted in r363688) with fixes
for the issue that caused it to be reverted.

Thanks to Arthur O'Dwyer for the patch.

Differential Revision: https://reviews.llvm.org/D58587

llvm-svn: 363968
2019-06-20 19:32:00 +00:00
Xing Xue ab4bcd844a AIX system headers need stdint.h and inttypes.h to be re-enterable
Summary:
AIX system headers need stdint.h and inttypes.h to be re-enterable when macro _STD_TYPES_T is defined so that limit macro definitions such as UINT32_MAX can be found. This patch attempts to allow that on AIX.

Reviewers: hubert.reinterpretcast, jasonliu, mclow.lists, EricWF

Reviewed by: hubert.reinterpretcast, mclow.lists

Subscribers: jfb, jsji, christof, cfe-commits, libcxx-commits, llvm-commits

Tags: #LLVM, #clang, #libc++

Differential Revision: https://reviews.llvm.org/D59253

llvm-svn: 363939
2019-06-20 15:36:32 +00:00
Louis Dionne 205ead8c16 [NFC][libc++] Remove stray semi-colon after function definition
llvm-svn: 363835
2019-06-19 16:33:28 +00:00
Zhihao Yuan 3f0ae625eb [libc++] Revert r363692 which implements P0608R3
The change caused a large number of compiler failures in
Google's codebase.  People need time to evaluate the impact.

llvm-svn: 363764
2019-06-19 07:11:08 +00:00
Eric Fiselier 5c739665a8 Remove GCC C++03 fallbacks for decltype and static_assert.
This means libc++ no longer needs to write extra braces in
static asserts: Ex `static_assert((is_same_v<T, V>), "msg")`.

llvm-svn: 363738
2019-06-18 20:50:25 +00:00
Marshall Clow 8dc6840f1c Fix the floating point version of midpoint. It wasn't constexpr, among other things. Add more tests. As a drive-by, the LCD implementation had a class named '__abs' which did a 'absolute value to a common-type' conversion. Rename that to be '__ct_abs'.
llvm-svn: 363714
2019-06-18 18:13:54 +00:00
Zhihao Yuan c74fc6d5f9 [libc++] Implement P0608R3 - A sane variant converting constructor
Summary:
Prefer user-defined conversions over narrowing conversions and conversions to bool.

References:
 http://wg21.link/p0608

Reviewers: EricWF, mpark, mclow.lists

Reviewed By: mclow.lists

Subscribers: zoecarver, ldionne, libcxx-commits, cfe-commits, christof

Differential Revision: https://reviews.llvm.org/D44865

llvm-svn: 363692
2019-06-18 15:26:50 +00:00
Louis Dionne 1fab01f92b [libc++] Revert the addition of map/multimap CTAD
This was found to be broken on Clang trunk. This is a revert of the
following commits (the subsequent commits added XFAILs to the tests
that were missing from the original submission):

    r362986: Implement deduction guides for map/multimap.
    r363014: Add some XFAILs
    r363097: Add more XFAILs
    r363197: Add even more XFAILs

llvm-svn: 363688
2019-06-18 14:40:15 +00:00
Mikhail Maltsev 411c630bae [libc++] Keep __regex_word in sync with ctype_base
Summary:
The class ctype_base in the header <__locale> contains masks for
character classification functions, which are kept in sync with
platform's C library, hence it contains many special cases.
The value of the bit mask __regex_word in the header <regex> must not
clash with those bit masks.

Currently the default case (i.e. unknown platform/C library) is
handled incorrectly: the __regex_word clashes with ctype_base::punct.

To avoid replicating the whole list of platforms in <regex> this patch
defines __regex_word in <__locale>, so that it is always kept in sync
with other masks.

Reviewers: ldionne, mclow.lists, EricWF

Reviewed By: ldionne

Subscribers: krytarowski, christof, dexonsmith, pbarrio, simon_tatham, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D63284

llvm-svn: 363363
2019-06-14 09:04:16 +00:00
Thomas Anderson 2ce370c957 [libc++] Fix build with gcc 4.8
gcc 4.8.4 (but not 5.4.0 or 7.3.0) has trouble initializing errc with {}, giving
the error in [1]. This CL switches to explicitly using errc(0), which gcc 4.8
accepts.

[1] https://bugs.chromium.org/p/chromium/issues/detail?id=973723

Differential Revision: https://reviews.llvm.org/D63296

llvm-svn: 363333
2019-06-13 22:27:24 +00:00
Eric Fiselier 5de7cacf07 Make GCC in C++03 Unsupported
Summary:
This patch make G++03 explicitly unsupported with libc++, as discussed on the mailing lists.


Below is the rational for this decision.
----------------------------------------------------------------------------------------------------

libc++ claims to support GCC with C++03 ("G++03"), and this is a problem for our users.

Our C++03 users are all using Clang. They must be.  Less than 9% of the C++03 tests pass with GCC [1][2]. No non-trivial C++ program could work.

Attempting to support G++03 impacts our QoI considerably. Unlike Clang, G++03 offers almost no C++11 extensions. If we could remove all the fallbacks for G++03, it would mean libc++ could::

* Improve Correctness:

Every `#ifdef _LIBCPP_HAS_NO_<C++11-feature>` is a bug manifest. It exists to admit for deviant semantics.

* Achieve ABI stability between C++03 and C++11

Differences between our C++03 and C++Rest branches contain ABI bugs. For example `std::nullptr_t` and `std::function::operator()(...)` are currently incompatible between C++11 and C++03, but could be fixed.

* Decrease Compile Times and Memory Usage:

Writing efficient SFINAE requires C++11. Using alias templates, libc++ could reduce the number of instantiations it produces substantially.

* Decrease Binary Size

Similar to the last point, G++03 forces metaprogramming techniques that emit more debug information [3] [4]. Compared to libstdc++, debug information size increases of +10% are not uncommon.

Reviewers: ldionne, mclow.lists, EricWF

Reviewed By: ldionne, EricWF

Subscribers: zoecarver, aprantl, dexonsmith, arphaman, libcxx-commits, #libc

Differential Revision: https://reviews.llvm.org/D63154

llvm-svn: 363219
2019-06-13 00:37:25 +00:00
Eric Fiselier 14d4869209 Apply [[nodebug]] to typedefs throughout the STL.
When applied to a typedef or alias template, the [[nodebug]] attribute
makes the typedef transparent to the debugger, so instead of seeing
`std::__function::__alloc_func<remove_reference<void(&)()>::type,
allocator<remove_reference<void(&)()>, void()>::_Target` you see
`void(&)()` as the type of the variable in your debugger.

Removing all this SFINAE noise from debug info has huge binary size
wins, in addition to improving the readability.

For now this change is on by default. Users can override it by
specifying -D_LIBCPP_NODEBUG_TYPE=

llvm-svn: 363117
2019-06-12 02:03:31 +00:00
Louis Dionne e20865c387 [libc++] Implement deduction guides for <set>
This is part of C++17's P0433.

Thanks to Arthur O'Dwyer for the patch.

Differential Revision: https://reviews.llvm.org/D58582

llvm-svn: 363090
2019-06-11 18:21:08 +00:00
Louis Dionne 405570dc7a [libcxx] Make std::tuple<> trivially constructible
Summary:
This is not mandated by the Standard, but it's nonetheless a nice
property to have, especially since it's so easy to implement. It
also shrinks our bug list!

PR41714

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D62618

llvm-svn: 363075
2019-06-11 15:02:10 +00:00
Louis Dionne 776acf225b [libcxx] Slightly improved policy for handling experimental features
Summary:
Following the discussion on the libcxx-dev mailing list
(http://lists.llvm.org/pipermail/libcxx-dev/2019-May/000358.html),
this implements the new policy for handling experimental features and
their deprecation. We basically add a deprecation warning for
std::experimental::filesystem, and we remove a bunch of <experimental/*>
headers that were now empty.

Reviewers: mclow.lists, EricWF

Subscribers: mgorny, christof, jkorous, dexonsmith, arphaman, libcxx-commits, jfb

Tags: #libc

Differential Revision: https://reviews.llvm.org/D62428

llvm-svn: 363072
2019-06-11 14:48:40 +00:00
Marshall Clow edfe8525de Implement deduction guides for map/multimap. Reviewed as https://reviews.llvm.org/D58587. Thanks to Quuxplusone for the submission.
llvm-svn: 362986
2019-06-10 21:28:23 +00:00
Eric Fiselier d63dd874ec Substantially reduce instantiations and debug size of std::function
std::function uses a standard allocator to manage its memory, however
standard allocators are templates and using them correctly requires
a stupid amount of instantiations. This leads to a substantial increase
in debug info and object sizes.

This patch addresses the issue by dropping the allocator when possible
and using raw new and delete to get memory.

This change decreases the object file size for the test func.wrap.func.con/F.pass.cpp by 33% and the final binary by 29% (when compiled with -g -ggnu-pubnames -gpubnames).

It also roughly halfs the number of entries in the pubnames and pubtype
sections.

llvm-svn: 362865
2019-06-08 01:31:19 +00:00
Marshall Clow f67524d400 We had a _LIBCPP_ASSERT commented out because gcc 4.9 didn't like it. We (LLVM) now require GCC 5.1, so that's not a problem any more. Re-enable the assertion. Fixes PR#36863
llvm-svn: 362465
2019-06-04 02:07:11 +00:00
Louis Dionne a2a1ec27d0 [NFC][libcxx] Remove trailing whitespace
It's incredibly annoying when trying to create diffs

llvm-svn: 361981
2019-05-29 16:01:36 +00:00
Marshall Clow 6b03a1b423 Add additional constraints on midpoint(pointer, pointer). Fixes PR#42037.
llvm-svn: 361970
2019-05-29 15:17:55 +00:00
Eric Fiselier 82705e7d52 Fix build breakage on 32-bit machines
llvm-svn: 361917
2019-05-29 02:38:19 +00:00
Eric Fiselier 2405bd6898 Rework std::type_info definition to support systems without fully
merged type info names.

Previously std::type_info always expected type info string to be unique.
But this isn't always the case. Like when -Bsymbolic is passed to the
linker or due to llvm.org/PR37398.

This patch adds the LIBCXX_HAS_MERGED_TYPEINFO_NAMES_DEFAULT CMake
option which, when specified, overrides the default configuration for
the library.

The current defaults still assume unique names even though this isn't
strictly correct for ELF binaries. We should consider changing the
default in a follow up commit.

llvm-svn: 361913
2019-05-29 02:21:37 +00:00
Marshall Clow 1efbe67414 Fix an incorrect 'Throws' in the regex code. Add a test for the new behavior. Reviewed as https://reviews.llvm.org/D61828. Thanks to Mark for the catch and the fix.
llvm-svn: 361887
2019-05-28 22:42:32 +00:00
Eric Fiselier ae02e89448 P0722R3: Implement library support for destroying delete
Summary:
This provides the `std::destroying_delete_t` declaration in C++2a and after. (Even when the compiler doesn't support the language feature).

However, the feature test macro `__cpp_lib_destroying_delete` is only defined when we have both language support and  C++2a.


Reviewers: ldionne, ckennelly, serge-sans-paille, EricWF

Reviewed By: EricWF

Subscribers: dexonsmith, riccibruno, christof, jwakely, jdoerfert, mclow.lists, ldionne, libcxx-commits

Differential Revision: https://reviews.llvm.org/D55840

llvm-svn: 361572
2019-05-23 23:46:44 +00:00
Chris Bieneman c5ec2a2bc1 [CMake] Copy C++ headers before configuring runtimes build
Summary: On some platforms C++ headers are packaged with the compiler not the sysroot. If you don't copy C++ headers into the build include directory during configuraiton of the outer build the C++ check during the runtime configuration may get inaccurate results.

Reviewers: phosek, compnerd, smeenai, EricWF

Reviewed By: compnerd

Subscribers: EricWF, christof, libcxx-commits, mgorny, llvm-commits

Tags: #llvm, #libc

Differential Revision: https://reviews.llvm.org/D62155

llvm-svn: 361513
2019-05-23 17:06:46 +00:00
Marshall Clow d75a0450ad Ensure that hash<basic_string> uses char_traits. Fixes PR#41876. Reviewed as https://reviews.llvm.org/D61954
llvm-svn: 361201
2019-05-20 21:56:51 +00:00
Eric Fiselier 236317d216 Fix missing std:: qualifier in __gnu_cxx::hash_map in C++03
llvm-svn: 361075
2019-05-17 20:59:57 +00:00
Eric Fiselier 549ddae58f Remove `using namespace std;` in __gnu_cxx namespace.
The `using namespace std;` opens us up to ambiguity
when any of the std:: names are also present in the global namespace.
Instead we should properly qualify names we use from std::.

llvm-svn: 361074
2019-05-17 20:46:00 +00:00
Marshall Clow 51497fb8b3 Mark private function __sign as constexpr.
llvm-svn: 360167
2019-05-07 16:07:24 +00:00
Eric Fiselier ac6843cea2 Remove unneeded <algorithm> include in cmath.
It's a remnant from an earlier version of the lerp change
and is unneeded.

llvm-svn: 360098
2019-05-06 23:14:31 +00:00
Dan Gohman 3efd6e37e4 [WebAssembly] WASI support for libcxx
This adds explicit support for the WASI platform to libcxx.

WASI libc uses some components from musl, however it's not fully compatible
with musl, so we're planning to stop using _LIBCPP_HAS_MUSL_LIBC and
customize for WASI libc specifically.

Differential Revision: https://reviews.llvm.org/D61336

Reviewers: sbc100, ldionne
llvm-svn: 359703
2019-05-01 16:47:30 +00:00
Eric Fiselier 71aa67506b Support overaligned types in `aligned_storage`.
Summary:
The current implementation of aligned storage was written before we had `alignas`, so it used a list of builtin types to force the alignment. But this doesn't work overaligned requests.

This patch adds a fallback case supporting over-alignment. It only affects case that were previously ill-formed.

Reviewers: rsmith, ldionne, dlj, mclow.lists

Reviewed By: mclow.lists

Subscribers: mclow.lists, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D61301

llvm-svn: 359596
2019-04-30 18:44:45 +00:00
Marshall Clow 39084db328 Implement LWG 2960: nonesuch is insufficiently useless
llvm-svn: 359526
2019-04-30 00:54:38 +00:00
Marshall Clow c29db2d83e Add '_LIBCPP_ASSERT(ready())' to several match_results method that have this precondtion. Fix several tests which did not honor this precondition. Thanks to Andrey Maksimov for pointing this out.
llvm-svn: 359324
2019-04-26 17:10:03 +00:00
Eric Fiselier 7e528bc4ce Fix return type of std::tuple_cat.
When the arguments to tuple cat were const, the const was incorrectly
propagated into the type of the resulting tuple. For example:

const std::tuple<int> t(42);
auto r = std::tuple_cat(t, t);
// Incorrect! should be std::tuple<int, int>.
static_assert(is_same_v<decltype(r), std::tuple<const int, const int>>);

llvm-svn: 359255
2019-04-26 01:02:18 +00:00
Richard Smith de329354aa Remove incorrect explicit instantiation declarations for valarray
libc++ ABI v1 provides three valarray symbols as part of the shared library:

valarray<size_t>::valarray(size_t)
valarray<size_t>::~valarray()
valarray<size_t>::resize(size_t, size_t)

The first two of these are intended to be removed in V2 of the ABI: they're
attributed _LIBCPP_HIDE_FROM_ABI_AFTER_V1, and  it appears that the intention
is that these symbols from the library are not used even when building using
the V1 ABI. However, there are explicit instantiation declarations for all
three symbols in the header, which are not correct as we do not intend to find
an instantiation of these functions that is provided elsewhere.

(A recent change to clang to properly diagnose explicit instantiation
declarations of internal linkage functions -- required by [temp.explicit]p13 --
had to be rolled back because it diagnosed these explicit instantiations.)

Remove the explicit instantiation declarations, and remove the explicit
instantiation definitions for V2 of the libc++ ABI onwards.

llvm-svn: 359243
2019-04-25 21:31:58 +00:00
Richard Smith ae62727a28 Remove libc++ checks and workarounds for unsupported old versions of GCC (<4.9).
Differential Revision: https://reviews.llvm.org/D61107

llvm-svn: 359232
2019-04-25 20:02:10 +00:00
Richard Smith 65d4d5e9e7 Fix buildbot failures after r359159.
std::mutex was not actually is_nothrow_default_constructible in C++98/C++03,
because the variable declaration

  std::mutex M;

... could throw an exception from the mutex destructor. Fix it by marking the
destructor as non-throwing. This has no effect in C++11 onwards, because
destructors are non-throwing by default in those language modes.

llvm-svn: 359229
2019-04-25 20:00:06 +00:00
Martin Storsjo 2bbb7feda8 Set _LIBCPP_DLL_VIS on _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS in MinGW mode
Contrary to MSVC, MinGW compilers wants the dllexport attribute on
the declaration of an explicit template instantiation, not on the
definition.

Differential Revision: https://reviews.llvm.org/D61123

llvm-svn: 359227
2019-04-25 19:46:28 +00:00
Marshall Clow b0e2daf64b Implement 'lerp'; which is the last bit of P0811. Mark that paper as complete.
llvm-svn: 359211
2019-04-25 17:44:18 +00:00
Marshall Clow d3d0ecbfd5 Implement midpoint for floating point types. Reviewed as https://reviews.llvm.org/D61014.
llvm-svn: 359184
2019-04-25 12:11:43 +00:00
Richard Smith d8b01111a0 Use modern type trait implementations when available.
Teach libcxx to stop using various deprecated __has_* type traits, in favor of
the ("modern", C++11 era) __is_* type traits.

This is mostly just a simplification, but fixes at least one bug: _Atomic T
should be considered trivially-destructible, but is not considered to be POD by
Clang, and __has_trivial_destructor is specified in the GCC documentation as
returning false for non-POD non-class types.

Differential Revision: https://reviews.llvm.org/D48292

llvm-svn: 359159
2019-04-25 00:35:01 +00:00
Eric Fiselier 2fc5a786be Add std::is_constant_evaluated.
Clang recently added __builtin_is_constant_evaluated() and GCC 9.0
has it as well.

This patch adds support for it in libc++.

llvm-svn: 359119
2019-04-24 17:54:25 +00:00
Eric Fiselier 6886f1e39b Avoid name conflict with kernel headers
llvm-svn: 359080
2019-04-24 09:43:44 +00:00
Eric Fiselier 1670772adc Fix implementation of ::abs and std::abs LWG 2192.
Summary:
All overloads of `::abs` and `std::abs` must be present in both `<cmath>` and `<cstdlib>`. This is problematic to implement because C defines `fabs` in `math.h` and `labs` in `stdlib.h`. This introduces a circular dependency between the two headers. 

This patch implements that requirement by moving `abs` into `math.h` and making `stdlib.h` include `math.h`. In order to get the underlying C declarations from the "real" `stdlib.h` inside our `math.h` we need some trickery. Specifically we need to make `stdlib.h` include next itself.

Suggestions for a cleaner implementation are welcome.

Reviewers: mclow.lists, ldionne

Reviewed By: ldionne

Subscribers: krytarowski, fedor.sergeev, dexonsmith, jdoerfert, jsji, libcxx-commits

Differential Revision: https://reviews.llvm.org/D60097

llvm-svn: 359020
2019-04-23 18:01:58 +00:00
Thomas Anderson 6ab51de08e [libc++] Make __debug_less::operator() constexpr
This is a followup to [1] which added a new `__debug_less::operator()` overload.
[2] added `_LIBCPP_CONSTEXPR_AFTER_CXX17` to the original
`__debug_less::operator()` between the time of writing [1] and landing it.  This
change adds `_LIBCPP_CONSTEXPR_AFTER_CXX17` to the new overload too.

[1] https://reviews.llvm.org/rL358423
[2] https://reviews.llvm.org/rL358252

Differential Revision: https://reviews.llvm.org/D60724

llvm-svn: 358725
2019-04-19 00:52:54 +00:00
Louis Dionne ebaf1d5e2b [libc++] Unconditionally enable the __pad_and_output optimization
This used to be guarded on whether the deployment target was greater
than macosx10.8, however testing against the dylibs for 10.8 and earlier
with the function enabled works too. The revision that introduced
__pad_and_output is r164241 and it does not mention a reason for the
guard.

llvm-svn: 358677
2019-04-18 15:19:35 +00:00
Louis Dionne 81875a67b0 [libc++] Use the no_destroy attribute to avoid destroying debug DB statics
Summary:
Otherwise, we can run into problems when the program has static variables
that need to use the debug database during their deinitialization, if
the debug DB has already been deinitialized.

Reviewers: EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D60830

llvm-svn: 358602
2019-04-17 18:20:19 +00:00
Eric Fiselier c3d6a929fd Fix visibility for coroutine types on Windows
llvm-svn: 358551
2019-04-17 04:31:46 +00:00
Marshall Clow 896b0c7b99 Fix list/forward_list implementations of remove_if and unique to deal with predicates that are part of the sequence passed in. We already do this for remove.
llvm-svn: 358534
2019-04-16 22:11:26 +00:00
Thomas Anderson 3c3ccc0049 [libc++] Fix build failure with _LIBCPP_DEBUG=0 when iterators return values instead of references
There are many STL algorithms (such as lexicographical_compare) that compare
values pointed to by iterators like so:
    __comp(*it1, *it2);
	
When building with `_LIBCPP_DEBUG=0`, comparators are wrapped in `__debug_less`
which does some additional validation.  But `__debug_less::operator()` takes
non-const references, so if the type of `*it1` is int, not int&, then the build
will fail.

This change adds a `const&` overload for `operator()` to fix the build.

Differential Revision: https://reviews.llvm.org/D60592

llvm-svn: 358423
2019-04-15 17:02:15 +00:00
Eric Fiselier aa1cad1591 Cleanup how debug comparators are created in <algorithm>
Instead of having an `#if` block in every algorithm using a debug
comparator, this patch introduces the __comp_ref_type trait that
selects __debug_less in debug mode and _Comp& otherwise.

This patch should have no observable functionality change.

llvm-svn: 358252
2019-04-12 05:18:19 +00:00
Louis Dionne 7c142fcc06 [libc++] Make sure we don't eagerly diagnose non-const comparators for containers of incomplete types
Summary:
In r348529, I improved the library-defined diagnostic for using containers
with a non-const comparator/hasher. However, the check is now performed
too early, which leads to the diagnostic being emitted in cases where it
shouldn't. See PR41360 for details.

This patch moves the diagnostic to the destructor of the containers, which
means that the diagnostic will only be emitted when the container is instantiated
at a point where the comparator and the key/value are required to be complete.
We still retain better diagnostics than before r348529, because the diagnostics
are performed in the containers themselves instead of __tree and __hash_table.

As a drive-by fix, I improved the diagnostic to mention that we can't find
a _viable_ const call operator, as suggested by EricWF in PR41360.

Reviewers: EricWF, mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits, zoecarver

Tags: #libc

Differential Revision: https://reviews.llvm.org/D60540

llvm-svn: 358189
2019-04-11 16:14:56 +00:00
Louis Dionne 396145d0da [libc++] Fix error flags and exceptions propagated from input stream operations
Summary:
This is a re-application of r357533 and r357531. They had been reverted
because we thought the commits broke the LLDB data formatters, but it
turns out this was because only r357531 had been included in the CI
run.

Before this patch, we would only ever throw an exception if the badbit
was set on the stream. The Standard is currently very unclear on how
exceptions should be propagated and what error flags should be set by
the input stream operations. This commit changes libc++ to behave under
a different (but valid) interpretation of the Standard. This interpretation
of the Standard matches what other implementations are doing.

This effectively implements the wording in p1264r0. It hasn't been voted
into the Standard yet, however there is wide agreement that the fix is
correct and it's just a matter of time before the fix is standardized.

PR21586
PR15949
rdar://problem/15347558

Reviewers: mclow.lists, EricWF

Subscribers: christof, dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D49863

llvm-svn: 357775
2019-04-05 16:33:37 +00:00
Nico Weber 1362d7ef88 libcxx: Add _LIBCPP_NODISCARD_EXT to 38 more functions
This builds on the work done in r342808 and adds _LIBCPP_NODISCARD_EXT
to 37 more functions, namely:

adjacent_find, all_of, any_of, binary_search, clamp, count_if, count,
equal_range, equal, find_end, find_first_not_of, find_first_of, find_if,
find, includes, is_heap_until, is_heap, is_partitioned, is_permutation,
is_sorted_until, is_sorted, lexicographical_compare, lower_bound,
max_element, max, min_element, min, minmax_element, minmax, mismatch,
none_of, remove_if, remove, search_n, search, unique, upper_bound

The motivation here is that we noticed that find_if is nodiscard with
Visual Studio's standard library, and we deemed that useful
(https://crbug.com/948122).
https://devblogs.microsoft.com/cppblog/c17-progress-in-vs-2017-15-5-and-15-6/
says "Our criteria for emitting the warning are: discarding the return
value is a guaranteed leak [...], discarding the return value is
near-guaranteed to be incorrect (e.g. remove()/remove_if()/unique()), or
the function is essentially a pure observer (e.g. vector::empty() and
std::is_sorted())." so I went through algorithm and tried to apply these
criteria.

Some of these, like vector::empty() are already nodiscard per C++
standard and didn't need changing.

I didn't (yet?) go over std::string::find* methods which should probably
have _LIBCPP_NODISCARD_EXT too (but not as part of this change).

Differential Revision: https://reviews.llvm.org/D60145

llvm-svn: 357619
2019-04-03 18:13:08 +00:00
Louis Dionne 6c49e1ce26 [libc++] Use std::is_nothrow_callable for std::invoke according to LWG 2807
Thanks to Zoe Carver for the patch.
Differential Revision: https://reviews.llvm.org/D58097

llvm-svn: 357616
2019-04-03 17:54:37 +00:00
Louis Dionne 3b8c90b80d [libc++] (Take 2) Correctly handle Objective-C++ ARC qualifiers in std::is_pointer
Summary:
Otherwise, std::is_pointer<id __strong> works, but std::is_pointer<id __weak>
(and others) don't work as expected.

The previous patch (r357517) had to be reverted in r357569 because it
broke the Chromium build. This patch shouldn't have the same problem.

rdar://problem/49126333

Reviewers: ahatanak, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D60087

llvm-svn: 357586
2019-04-03 14:29:52 +00:00
Hans Wennborg e475c89700 Revert "[libc++] Correctly handle Objective-C++ ARC qualifiers in std::is_pointer"
This broke the Chromium build on Mac, see https://crbug.com/949071

> Summary:
> Otherwise, std::is_pointer<id __strong> works, but std::is_pointer<id __weak>
> (and others) don't work as expected.
>
> rdar://problem/49126333
>
> Reviewers: ahatanak, EricWF
>
> Subscribers: christof, jkorous, dexonsmith, libcxx-commits
>
> Differential Revision: https://reviews.llvm.org/D60087

llvm-svn: 357569
2019-04-03 10:07:37 +00:00
Marshall Clow 0583d9ea8d Fix backwards test that I committed yesterday. Sigh
llvm-svn: 357540
2019-04-03 00:01:03 +00:00
Louis Dionne 38b7e74836 Revert "[libc++] Fix error flags and exceptions propagated from input stream operations"
This reverts commits r357533 and r357531, which broke the LLDB
data formatters. I'll hold off until we know how to fix the data
formatters accordingly.

llvm-svn: 357536
2019-04-02 22:21:27 +00:00
Louis Dionne 00f6cfe908 [libc++] Fix build when exceptions are turned off
llvm-svn: 357533
2019-04-02 22:02:17 +00:00
Louis Dionne 1754774369 [libc++] Fix error flags and exceptions propagated from input stream operations
Summary:
Before this patch, we would only ever throw an exception if the badbit
was set on the stream. The Standard is currently very unclear on how
exceptions should be propagated and what error flags should be set by
the input stream operations. This commit changes libc++ to behave under
a different (but valid) interpretation of the Standard. This interpretation
of the Standard matches what other implementations are doing.

I will submit a paper in San Diego to clarify the Standard such that the
interpretation used in this commit (and other implementations) is the only
possible one.

PR21586
PR15949
rdar://problem/15347558

Reviewers: mclow.lists, EricWF

Subscribers: christof, dexonsmith, cfe-commits

Differential Revision: https://reviews.llvm.org/D49863

llvm-svn: 357531
2019-04-02 21:43:07 +00:00
Louis Dionne aac9285377 [libc++] Correctly handle Objective-C++ ARC qualifiers in std::is_pointer
Summary:
Otherwise, std::is_pointer<id __strong> works, but std::is_pointer<id __weak>
(and others) don't work as expected.

rdar://problem/49126333

Reviewers: ahatanak, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D60087

llvm-svn: 357517
2019-04-02 19:48:39 +00:00
Louis Dionne 6cd8126360 [libc++] Remove use of auto with actual type
For compatibility with C++03.

llvm-svn: 357512
2019-04-02 19:20:47 +00:00
Louis Dionne f401a749e1 [libc++][NFC] Remove useless public: label at the end of class
llvm-svn: 357511
2019-04-02 19:11:22 +00:00
Marshall Clow 3bf63cf3b3 Special case some duration arithmetic for GCC and PPC because their long double constant folding is broken. Fixes PR#39696.
llvm-svn: 357478
2019-04-02 14:46:36 +00:00
Eric Fiselier 0657197588 Fix a number of bugs in __val_expr's subset operator[].
The current definitions were entirely broken. They didn't call any
existing constructor and the forgot to friend the expression types they
were trying to construct.

llvm-svn: 357453
2019-04-02 08:05:23 +00:00
Louis Dionne 2b0c7abba3 [libc++] Declare std::tuple_element as struct instead of class
Similarly to https://reviews.llvm.org/rL350972, this revision changes
std::tuple_element from class to struct.

Fixes PR41331.
Thanks to Jan Wilken Dörrie for the patch.

Differential Revision: https://reviews.llvm.org/D60069

llvm-svn: 357411
2019-04-01 16:39:34 +00:00
Marshall Clow efa6d803c6 Fix PR41130 - 'operator/ of std::chrono::duration and custom type'. Thanks to Zulan for the report, and Howard for the direction of the fix.
llvm-svn: 357410
2019-04-01 16:38:02 +00:00
Eric Fiselier b0e79823d6 Make common_type's implementation common
Summary:
Currently the C++03 implementation of common_type has much different behavior than the C++11 one. This causes bugs, including inside `<chrono>`.

This patch unifies the two implementations as best it can. The more code they share, the less their behavior can diverge. 

Reviewers: mclow.lists, ldionne, sbenza

Reviewed By: mclow.lists, ldionne

Subscribers: libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D59678

llvm-svn: 357370
2019-03-31 20:49:06 +00:00
Eric Fiselier 0706e144d5 Mark fenv.h as a system header before the #include_next directive
This fixes a -Wgnu-include-next warning

Patch by dmauro.

llvm-svn: 357267
2019-03-29 16:03:57 +00:00
Marshall Clow 1931c4306a Fix PR#35967: '<regex> syntax_option_type is not a proper bitmask' Sadly, this is an ABI break, so it's only available if you define either '_LIBCPP_ABI_VERSION > 2' or '_LIBCPP_ABI_UNSTABLE' or '_LIBCPP_ABI_REGEX_CONSTANTS_NONZERO' and rebuild your dylib.
llvm-svn: 357190
2019-03-28 17:30:23 +00:00
Louis Dionne 7cd0dad834 [libc++] Rename span's as_writeable_bytes to as_writable_bytes
Summary: The Standard says as_writable_bytes.

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D59882

llvm-svn: 357139
2019-03-28 01:27:52 +00:00
Thomas Anderson 24812d8ac4 Fix and speedup __libcpp_locale_guard on Windows
The old implementation assumed the POSIX `setlocale()` API where the old
locale is returned.  On Windows, the _new_ locale is returned.  This meant
that `__libcpp_locale_guard` wasn't resetting the locale on destruction.

The new implementation fixes the above issue and takes advantage of
`setlocale(LC_ALL)` to reduce the number of calls, and also avoids setting
the locale at all if it's not necessary.

Differential Revision: https://reviews.llvm.org/D59572

llvm-svn: 357104
2019-03-27 18:09:30 +00:00
Brian Gesiak b66754a29e Revert "[coroutines] Add std::experimental::task<T> type"
This revision is causing build and test failures, such as
http://lab.llvm.org:8011/builders/libcxx-libcxxabi-libunwind-armv8-linux/builds/648/steps/test.libcxx/logs/stdio,
so I'll revert it.

llvm-svn: 357023
2019-03-26 19:50:46 +00:00
Brian Gesiak 57839425aa [coroutines] Add std::experimental::task<T> type
Summary:
Adds the coroutine `std::experimental::task<T>` type described in proposal P1056R0.
See https://wg21.link/P1056R0.

This implementation allows customization of the allocator used to allocate the
coroutine frame by passing std::allocator_arg as the first argument, followed by
the allocator to use.

This supports co_awaiting the same task multiple times. The second and
subsequent times it returns a reference to the already-computed value.

This diff also adds some implementations of other utilities that have potential for
standardization as helpers within the test/... area:
- `sync_wait(awaitable)` - See P1171R0
- `manual_reset_event`

Move the definition of the __aligned_allocation_size helper function
from <experimental/memory_resource> to <experimental/__memory>
so it can be more widely used without pulling in memory_resource.

Outstanding work:
- Use C++14 keywords directly rather than macro versions
  eg. use `noexcept` instead of `_NOEXCEPT`).
- Add support for overaligned coroutine frames.
  This may need wording in the Coroutines TS to support passing the extra `std::align_val_t`.
- Eliminate use of `if constexpr` if we want it to compile under C++14.

Patch by @lewissbaker (Lewis Baker).

llvm-svn: 357010
2019-03-26 17:46:06 +00:00
Marshall Clow 36db489874 Cleaup of requirements for optional. While researching LWG3196, I realized that optional did not reject 'const in_place_t' like it should. Added a test as well, and a check for arrays (which were already disallowed, but now we get a better error message). Should not affect anyone's code.
llvm-svn: 356918
2019-03-25 16:35:59 +00:00
Marshall Clow e1cd11d80f Fix a minor bug with std::next and prev not and negative numbers. In particular, std::prev cannot require Bidirectional Iterators, because you might 'go back' -1 places, which goes forward. Thanks to Ville and Jonathan for the bug report.
llvm-svn: 356818
2019-03-22 22:32:20 +00:00
Eric Fiselier 0e04ab7e94 Remove type visibility specifiers from new chrono types.
_LIBCPP_TYPE_VIS is only really needed on types with a vtable.
And on Windows it doesn't work with types that have only inline methods.

This patch removes the unneeded attributes.

llvm-svn: 356637
2019-03-21 01:48:15 +00:00
Nico Weber 0fd00a581d libc++/win: Make once_flag have the same size as a pointer.
`unsigned long` is 32-bit on 32-bit systems and 64-bit on 64-bit systems
on LP64 systems -- which most Unix systems are, but Windows isn't.
Windows is LLP64, which means unsigned long is 32-bit even on 64-bit
systems.

pplwin.h contains

    static_assert(alignof(void *) == alignof(::std::once_flag), ...)

which fails due to this problem.

Instead of unsigned long, use uintptr_t, which consistently is 32-bit
on 32-bit systems and 64-bit on 64-bit systems.

No functional change except on 64-bit Windows.

Differential Revision: https://reviews.llvm.org/D59607

llvm-svn: 356624
2019-03-20 22:55:03 +00:00
Louis Dionne fa0573027f [libc++] Mark <filesystem> as unavailable on Apple platforms using pragmas
Summary:
Also add the corresponding XFAILs to tests that require filesystem.
The approach taken to mark <filesystem> as unavailable in this patch
is to mark all the header as unavailable using #pragma clang attribute.
Marking each declaration using the attribute is more intrusive and
does not provide a lot of value right now because pretty much everything
in <filesystem> requires dylib support, often transitively.

This is an alternative to https://reviews.llvm.org/D59093.
A similar (but partial) patch was already applied in r356558.

Reviewers: mclow.lists, EricWF, serge-sans-paille

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D59224

llvm-svn: 356616
2019-03-20 21:18:14 +00:00
Marshall Clow 769c2459d5 Make to_chars/from_chars work back to C++11. This means that we can use them to implement to_string as well. Reviewed as https://reviews.llvm.org/D59598.
llvm-svn: 356585
2019-03-20 18:13:23 +00:00
Louis Dionne 77bca6d296 [NFC] Fix a couple of typos in libc++'s __config
llvm-svn: 356574
2019-03-20 17:05:52 +00:00
Louis Dionne b38c08ac02 [libc++] Mark <filesystem> tests as failing when the dylib doesn't support filesystem
This fixes CI for back-deployment testers on platforms that don't have
<filesystem> support in the dylib.

This is effectively half of https://reviews.llvm.org/D59224. The other
half requires fixes in Clang.

llvm-svn: 356558
2019-03-20 14:34:00 +00:00
Eric Fiselier 33244990ad Add visibility attributes and inline to some vector methods.
Adding filesystem to the dylib caused some vector symbols to leak
into the set of exported symbols. This patch hides those symbols.

llvm-svn: 356502
2019-03-19 19:19:44 +00:00
Louis Dionne afd1a23ffb [libc++] Mark internal types of std::filesystem as hidden
Summary:
Otherwise, implicit instantiations of templates with these types can
cause the dylib to start exporting the vtable/RTTI of the instantiation.
Giving hidden visibility to those types causes the compiler to understand
that they are not used outside the dylib, and as a result implicitly
instantiated vtables/RTTI of templates with those internal types will
get hidden visibility.

Reviewers: EricWF

Subscribers: christof, jkorous, dexonsmith, jdoerfert, libcxx-commits

Differential Revision: https://reviews.llvm.org/D59550

llvm-svn: 356488
2019-03-19 17:47:53 +00:00
Marshall Clow 9ea0e473f0 Mark 'front()' and 'back()' as noexcept for array/deque/string/string_view. These are just rebranded 'operator[]', and should be noexcept like it is.
llvm-svn: 356435
2019-03-19 03:30:07 +00:00
Eric Fiselier 61b302f94f Remove exception throwing debug mode handler support.
Summary:
The reason libc++ implemented a throwing debug mode handler was for ease of testing. Specifically,
I thought that if a debug violation aborted, we could only test one violation per file. This made
it impossible to test debug mode. Which throwing behavior we could test more!

However, the throwing approach didn't work either, since there are debug violations underneath noexcept
functions. This lead to the introduction of `_NOEXCEPT_DEBUG`, which was only noexcept when debug
mode was off.

Having thought more and having grown wiser, `_NOEXCEPT_DEBUG` was a horrible decision. It was
viral, it didn't cover all the cases it needed to, and it was observable to the user -- at worst
changing the behavior of their program.

  This patch removes the throwing debug handler, and rewrites the debug tests using 'fork-ing' style
  death tests.

Reviewers: mclow.lists, ldionne, thomasanderson

Reviewed By: ldionne

Subscribers: christof, arphaman, libcxx-commits, #libc

Differential Revision: https://reviews.llvm.org/D59166

llvm-svn: 356417
2019-03-18 21:50:12 +00:00
Marshall Clow 5bcca9ffd1 Mark vector::operator[] and front/back as noexcept. We already do this for string and string_view. This should give better codegen inside of noexcept functions. Add tests for op[]/front/back/at, because apparently we had none.
llvm-svn: 356224
2019-03-15 00:29:35 +00:00
Marshall Clow 5f6a5ac19c Add noexcept to operator[] for array and deque. This is an extension. We already do this for string and string_view. This should give better codegen inside of noexcept functions.
llvm-svn: 356209
2019-03-14 21:56:57 +00:00
Marshall Clow 330ab33f7c Add std::midpoint for integral and poiner types. Described in P0811, reviewed as D59099.
llvm-svn: 356162
2019-03-14 16:25:55 +00:00
Eric Fiselier dfce2dd21e Properly constrain basic_string(Iter, Iter, Alloc = A())
llvm-svn: 356140
2019-03-14 12:31:10 +00:00
Louis Dionne a470a13a70 [libc++] Enable deprecation warnings by default
Summary:
In r342843, I added deprecation warnings to some facilities that were
deprectated in C++14 and C++17. However, those deprecation warnings
were not enabled by default.

After discussing this on IRC, we had finally gotten consensus to enable
those warnings by default, and I'm getting around to doing that only
now.

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, jdoerfert, libcxx-commits

Differential Revision: https://reviews.llvm.org/D58140

llvm-svn: 355961
2019-03-12 20:10:06 +00:00
Eric Fiselier 86af6f5088 Allow optional to tolerate being used with a nested class.
When Clang tries to complete a type containing `std::optional` it
considers the `in_place_t` constructor with no arguments which checks
if the value type is default constructible. If the value type is a
nested class type, then this check occurs too early and poisons the
is_default_constructible trait.

This patch makes optional deduce `in_place_t` so we can prevent
this early SFINAE evaluation. Technically this could break people
doing weird things with the in_place_t tag, but that seems less
important than making the nested class case work.

llvm-svn: 355877
2019-03-11 22:55:21 +00:00
Louis Dionne 3836a49039 [libc++] Remove empty header xlocale/xlocale.h
Summary:
I can't think of a reason for shipping this empty header. If there is
a reason to do so, then hopefully this review can uncover it.

Reviewers: mclow.lists, EricWF

Subscribers: mgorny, christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D59137

llvm-svn: 355829
2019-03-11 15:41:51 +00:00
Eric Fiselier 411210838d Work around dllimport bug with exclude_from_explicit_instantiation.
When dllimport is specified on a class, and
exclude_from_explicit_instatiation is specified on a member, clang-cl
will still expect a definition to be available externally. But this is
not correct.

Surprisingly one one symbol seems to be consistently affected by this
bug. So this patch simply works around it there.

llvm-svn: 355760
2019-03-08 23:59:29 +00:00
Eric Fiselier 3e3d6c9038 Fix C++03 build failure
llvm-svn: 355758
2019-03-08 23:30:26 +00:00
Eric Fiselier 0e1586c4fb Unbork `std::memory_order` ABI.
Summary:
We need to pin the underlying type of C++20' `std::memory_order` to match the C++17 version. Anything less is an ABI break.

At the moment it's `unsigned` before C++20 and `int` after. Or if you're using `-fshort-enums` it's `unsigned char` before C++20 and `int` after.

This patch explicitly specifies the underlying type of the  C++20 `memory_order` to be w/e type the compiler would have chosen for the C++17 version.

Reviewers: mclow.lists, ldionne

Reviewed By: ldionne

Subscribers: jfb, jdoerfert, #libc, zoecarver

Differential Revision: https://reviews.llvm.org/D59063

llvm-svn: 355755
2019-03-08 23:15:54 +00:00
Eric Fiselier 6e4ec6022f Fix PR41017 - Build failure with _LIBCPP_DEBUG=0 and non-const-ref
comparator for std::sort()

Our debug comparator assumed that the comparator it wraps would always
accepts the values by const ref. This isn't required by the standard.

This patch makes our __debug_less comparator forward the constness.

llvm-svn: 355752
2019-03-08 22:58:59 +00:00
Thomas Anderson 516d07de07 [libc++] Fix use-after-free when building with _LIBCPP_DEBUG=1
The issue is the following code:

    __cn1->__add(*__ip);
    (*__ip)->__c_ = __cn1;

`__ip` points into the array of iterators for container `__cn2`.  This code adds
the iterator to the array of iterators for `__cn1`, and updates the iterator to
point to the new container.

This code works fine, except when `__cn1` and `__cn2` are the same container.
`__cn1->__add()` might need to grow the array of iterators, and when it does,
`__ip` becomes invalid, so the second line becomes a use-after-free error.

Simply swapping the order of the above two lines is not sufficient, because of
the memmove() below.  The easiest and most performant solution is just to skip
touching any iterators if the containers are the same.

Differential Revision: https://reviews.llvm.org/D58926

llvm-svn: 355550
2019-03-06 21:10:08 +00:00
Eric Fiselier 2710d8e105 Fix ABI compatibility of `<stdexcept>` with VCRuntime.
Summary:
Currently, libc++'s `<stdexcept>` doesn't play nice with `vcruntime`. Specifically:

* `logic_error` and `runtime_error` have a different layout.
* libc++'s `logic_error` and `runtime_error` override `what()` but `vcruntime` does not.
*  `vcruntime` uses weak vtables for `<stdexcept>` types.
* libc++'s `<stdexcept>` constructors and assignment operators may have different manglings than `vcruntimes`.

This patch makes libc++'s declarations in `<stdexcept>` match those provided by MSVC's STL as closely as possible.
If MSVC doesn't declare a special member, then neither do we. This ensures that the implicit definitions have the same linkage, visibility, triviality, and noexcept-ness.







Reviewers: thomasanderson, ldionne, smeenai

Reviewed By: thomasanderson

Subscribers: jdoerfert, libcxx-commits

Differential Revision: https://reviews.llvm.org/D58945

llvm-svn: 355546
2019-03-06 20:31:57 +00:00
Louis Dionne 930007ba76 [libc++] Do not specify the underlying type of memory_order
Summary:
This breaks ABI for folks using -fshort-enums, and does not really buy
us anything.

http://llvm.org/PR40977

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits, zoecarver

Differential Revision: https://reviews.llvm.org/D59029

llvm-svn: 355521
2019-03-06 17:07:24 +00:00
Marshall Clow 8eda3ad29d Eradicate all the ptrdiff_ts in span left over from applying P1227. A couple of other minor cleanups. NFC
llvm-svn: 355481
2019-03-06 03:59:44 +00:00
Davide Italiano 6de760ac4e Reinstate libc++ patches now that the lldb formatter has been updated.
"[libc++] Fix <atomic> failures on GCC"
"[libc++] Change memory_order to an enum class"
"[libc++] decoupling Freestanding atomic<T> from libatomic.a"

llvm-svn: 355427
2019-03-05 18:40:49 +00:00
Davide Italiano 1061cb6a93 [libcxx] Revert set of atomic patches that broke lldb.
Revert "[libc++] Fix <atomic> failures on GCC"
Revert "[libc++] Change memory_order to an enum class"
Revert "[libc++] decoupling Freestanding atomic<T> from libatomic.a"

The lldb formatter nededs to be updated. Shafik and Louis will
coordinate to do so.

llvm-svn: 355417
2019-03-05 17:38:33 +00:00
Louis Dionne 130322e7cc [libc++] Fix <atomic> failures on GCC
Summary:
In https://reviews.llvm.org/D58201, we turned memory_order into an enum
class in C++20 mode. However, we were not casting memory_order to its
underlying type correctly for the GCC implementation, which broke the
build bots. I also fixed a test that was failing in C++17 mode on GCC 5.

Reviewers: EricWF, jfb, mclow.lists

Subscribers: zoecarver

Differential Revision: https://reviews.llvm.org/D58966

llvm-svn: 355409
2019-03-05 15:49:58 +00:00
Louis Dionne b55803283b [libc++] Change memory_order to an enum class
This implements P0439R0.

Thanks to Zoe Carver for the patch.
Differential Revision: https://reviews.llvm.org/D58201

llvm-svn: 355403
2019-03-05 14:50:25 +00:00
Eric Fiselier 1c014d75b4 Fix -fsanitize=vptr badness in <__debug>
Summary:

This patch fixes a lifetime bug when inserting a new container into the debug database. It is
diagnosed by UBSAN when debug mode is enabled. This patch corrects how nodes are constructed
during insertion.

The fix requires unconditionally breaking the debug mode ABI. Users should not expect ABI
stability from debug mode.

Reviewers: ldionne, serge-sans-paille, EricWF

Reviewed By: EricWF

Subscribers: mclow.lists, christof, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D58011

llvm-svn: 355367
2019-03-05 02:10:31 +00:00
Eric Fiselier e69290dc7f Make VCRuntime ABI configuration a first-class option.
Summary:
On Windows we currently provide two separate ABI configurations. One which defers to `vcruntime` to provide the C++ runtime and another which doesn't.
Using `vcruntime` allows interoperability which programs compiled against the MSVC STL, and should be preferred whenever possible.

When deferring to `vcruntime` much of the ABI we provide changes. Including the layout of `<stdexcept>` types, their vtables, and how the linkage of their members.

This patch introduces the `_LIBCPP_ABI_VCRUNTIME` macro to denote this configuration. It also cleans up the existing configuration for using `vcruntime`.

This cleanup lays the groundwork for fixing a number of ABI and interoperability bugs in  `<stdexcept>`.


Reviewers: thomasanderson, ldionne, smeenai

Reviewed By: smeenai

Subscribers: jdoerfert, libcxx-commits, #libc

Differential Revision: https://reviews.llvm.org/D58942

llvm-svn: 355366
2019-03-05 01:57:01 +00:00
Louis Dionne 21450545d1 [libc++] decoupling Freestanding atomic<T> from libatomic.a
This patch introduces non-lockfree atomics that do not require using
an external libatomic. This work is done with the long-term goal of
allowing the use of <atomic> in freestanding environments.

Thanks to Olivier Giroux for the patch.
Differential Revision: https://reviews.llvm.org/D56913

llvm-svn: 355318
2019-03-04 15:26:27 +00:00
Louis Dionne ab19068b7f [libc++] Add is_nothrow_convertible from P0758R1
Reviewed as https://reviews.llvm.org/D58019.
Thanks to Zoe Carver for the patch.

llvm-svn: 355010
2019-02-27 17:57:38 +00:00
Louis Dionne 1be935f418 [libc++] Remove visibility-related warnings with Clang 8
The attributes were placed incorrectly -- they need to be after the
"struct" keyword, not before.

llvm-svn: 355006
2019-02-27 17:33:25 +00:00
Marshall Clow 5c814099c7 I changed a 'enable_if<...>::type to' 'enable_if_t<...>' but forgot to remove the preceding 'typename'
llvm-svn: 354995
2019-02-27 16:09:35 +00:00
Marshall Clow 02e1651c1f Implment the last part of P1024: tuple-like interface to span. Reviewed as https://reviews.llvm.org/D58706.
llvm-svn: 354988
2019-02-27 15:41:37 +00:00
Marshall Clow 2ffa170515 In the review of D58642, Louis asked: 'Is there a reason for making this inline? Templates are already inline by default'. I told him that I didn't want to change the one call (ssize) that I was adding, but would come back later and clean them all (data/empty/begin/end/cbegin/cend/rbegin/rend/crbegin/crend/size/ssize) up later. Now it is later. Remove the unnecessary 'inline' modifiers from all these calls.
llvm-svn: 354952
2019-02-27 03:25:43 +00:00
Marshall Clow 7d3986ea30 Implement the second part of P1227R2 - Signed ssize() functions. Reviewed as https://reviews.llvm.org/D58642
llvm-svn: 354950
2019-02-27 02:58:56 +00:00
Marshall Clow 7ad06a9319 First part of P1227R2 - change span over to use 'size_t' instead of 'ptrdiff_t'. Reviewed as https://reviews.llvm.org/D58639.
llvm-svn: 354936
2019-02-27 00:32:16 +00:00
Marshall Clow 46c719ddcd Implement P1357: Traits for [Un]bounded Arrays; adopted in Kona
llvm-svn: 354891
2019-02-26 16:07:03 +00:00
Louis Dionne 5d79eaa82f [libc++] Rename _NOALIAS macro to _LIBCPP_NOALIAS
Summary:
For consistency, libc++ macros always start with _LIBCPP. This should
have no functionality change.

Reviewers: EricWF, mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D58558

llvm-svn: 354848
2019-02-26 06:34:42 +00:00
Marshall Clow 310b75e519 LWG3101 - span's Container constructors need another constraint. Reviewed as https://reviews.llvm.org/D57058.
llvm-svn: 354805
2019-02-25 18:32:57 +00:00
Marshall Clow 4fd0395477 Commit LWG3144 - span does not have a const_pointer typedef. Reviewed as D57039.
llvm-svn: 354802
2019-02-25 17:58:03 +00:00
Marshall Clow 9ab85a69dc First part of P1024: Usability Enhancements for std::span. Remove operator() for indexing, and add 'front' and 'back' calls.
llvm-svn: 354801
2019-02-25 17:54:08 +00:00
Dimitry Andric d95da99b91 Fix the build with gcc when `-Wredundant-decls` is passed
Summary:
gcc warns that `__throw_runtime_error` is declared both in `<__locale>`
and `<stdexcept>`, if `-Wredundant-decls` is passed on the command
line; this is the case with FreeBSD when ${WARNS} == 6.

Since `<__locale>` gets its first declaration via a transitive include
of `<stdexcept>`, and the second declaration is after the first
invocation of `__throw_runtime_error`, delete that second declaration.

Signed-off-by: Enji Cooper <yaneurabeya@gmail.com>

Reviewers: kristina, MaskRay, EricWF, ldionne, ngie

Reviewed By: EricWF

Subscribers: krytarowski, brooks, emaste, dim, christof, jdoerfert, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D58425

llvm-svn: 354515
2019-02-20 21:01:31 +00:00
Louis Dionne 7232a84e68 [libc++] Avoid UB in the no-exceptions mode in a few places
Summary:
A few places in the library seem to behave unexpectedly when the library
is compiled or used with exceptions disabled. For example, not throwing
an exception when a pointer is NULL can lead us to dereference the pointer
later on, which is UB. This patch fixes such occurences.

It's hard to tell whether there are other places where the no-exceptions
mode misbehaves like this, because the replacement for throwing an
exception does not always seem to be abort()ing, but at least this
patch will improve the situation somewhat.

See http://lists.llvm.org/pipermail/libcxx-dev/2019-January/000172.html

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D57761

llvm-svn: 353850
2019-02-12 16:06:02 +00:00
Eric Fiselier 9ebc9dbd3c Don't declare fenv.h functions when they're a macro.
libc still provides function declarations, and these declarations
conflict with libc++'s

llvm-svn: 353774
2019-02-12 00:05:14 +00:00
Eric Fiselier cf39dd44b8 Add fenv.h header
Summary:
Some implementations of fenv.h use macros to define the functions they provide. This can cause problems when `std::fegetround()` is spelled in source.

This patch adds a `fenv.h` header to libc++ for the sole purpose of turning those macros into real functions.

Reviewers: rsmith, mclow.lists, ldionne

Reviewed By: rsmith

Subscribers: mgorny, christof, libcxx-commits

Differential Revision: https://reviews.llvm.org/D57729

llvm-svn: 353767
2019-02-11 23:47:19 +00:00
Eric Fiselier e8adbae00a fix -Wextra-semi warnings
llvm-svn: 353650
2019-02-10 18:29:00 +00:00
Marshall Clow aa09911aef Add static_asserts to tuple's comparison operators to enforce the requirement that the tuples be the same size. See PR39183 for an example where we give unexpected results for this bad input case. With this change, we will reject it at compile-time
llvm-svn: 353450
2019-02-07 19:03:48 +00:00
Marshall Clow 954966c1af Add UBSAN annotation to __hash_table::rehash; we don't do anything wrong, but UBSAN's checker flags it as suspicious. See PR38606. NFC
llvm-svn: 353448
2019-02-07 18:53:58 +00:00
Marshall Clow c8879ab2fd Add a specialization for '__unwrap_iter' to handle const interators. This enables the 'memmove' optimization for std::copy, etc.
llvm-svn: 353311
2019-02-06 16:10:25 +00:00
Louis Dionne b3b8968117 [NFC][libc++] Reindent function
llvm-svn: 353180
2019-02-05 15:46:52 +00:00
Marshall Clow 2e719bc428 add a test and a couple minor bug fixes for the implicit-signed-integer-truncation sanitizer. This is PR#40566
llvm-svn: 352926
2019-02-01 21:59:27 +00:00
Louis Dionne 6b653fc70f [libc++] Disentangle the 3 implementations of type_info
Summary:
We currently have effectively 3 implementations of type_info: one for
the Microsoft ABI, one that does not assume that there's a unique copy
of each RTTI in a progran, and one that assumes a unique copy.

Those 3 implementations are entangled into the same class with nested
ifdefs, which makes it very difficult to understand. Furthermore, the
benefit of doing this is rather small since the code that is duplicated
across implementations is just a couple of trivial lines.

This patch stamps out the 3 versions of type_info explicitly to increase
readability. It also explains what's going on with short comments, because
it's far from obvious.

Reviewers: EricWF, mclow.lists

Subscribers: christof, jkorous, dexonsmith

Differential Revision: https://reviews.llvm.org/D57606

llvm-svn: 352905
2019-02-01 20:00:13 +00:00
Thomas Anderson 13447450bc [libc++] Don't define operator new/delete when using vcruntime
Fixes build errors on Windows without libc++abi of the form:

    new(173,36):  error: redeclaration of 'operator delete' cannot add 'dllexport' attribute
    _LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete(void* __p) _NOEXCEPT;
    vcruntime_new.h(87,16):  note: previous declaration is here
    void __CRTDECL operator delete(
    new(205,70):  error: redefinition of 'operator new'
    _LIBCPP_NODISCARD_AFTER_CXX17 inline _LIBCPP_INLINE_VISIBILITY void* operator new  (std::size_t, void* __p) _NOEXCEPT {return __p;}
    vcruntime_new.h(184,28):  note: previous definition is here
        inline void* __CRTDECL operator new(size_t _Size, _Writable_bytes_(_Size) void* _Where) noexcept
    new(206,70):  error: redefinition of 'operator new[]'
    _LIBCPP_NODISCARD_AFTER_CXX17 inline _LIBCPP_INLINE_VISIBILITY void* operator new[](std::size_t, void* __p) _NOEXCEPT {return __p;}
    vcruntime_new.h(199,28):  note: previous definition is here
        inline void* __CRTDECL operator new[](size_t _Size,
    new(207,40):  error: redefinition of 'operator delete'
    inline _LIBCPP_INLINE_VISIBILITY void  operator delete  (void*, void*) _NOEXCEPT {}
    vcruntime_new.h(190,27):  note: previous definition is here
        inline void __CRTDECL operator delete(void*, void*) noexcept
    new(208,40):  error: redefinition of 'operator delete[]'
    inline _LIBCPP_INLINE_VISIBILITY void  operator delete[](void*, void*) _NOEXCEPT {}
    vcruntime_new.h(206,27):  note: previous definition is here
        inline void __CRTDECL operator delete[](void*, void*) noexcept

Differential Revision: https://reviews.llvm.org/D57362

llvm-svn: 352647
2019-01-30 19:08:32 +00:00
Thomas Anderson 7f50dfa6fc [libc++] Fix Windows build error in <functional>
On my Windows system, __allocator is defined to nothing.  This change fixes build errors of the below form:

    In file included from algorithm:644:
    functional(1492,31):  error: expected member name or ';' after declaration specifiers
        const _Alloc& __allocator() const { return __f_.second(); }

Differential Revision: https://reviews.llvm.org/D57355

llvm-svn: 352561
2019-01-29 23:19:45 +00:00
Thomas Anderson db9152c248 [libc++] Fix Windows build error in include/filesystem
_LIBCPP_FUNC_VIS is redundant since the class is already annotated with
_LIBCPP_EXCEPTION_ABI.

Fixes this build error:

    In file included from fstream:188:
    filesystem(1350,3):  error: attribute 'dllimport' cannot be applied to member of 'dllimport' class
      _LIBCPP_FUNC_VIS
    __config(674,37):  note: expanded from macro '_LIBCPP_FUNC_VIS'
    #define _LIBCPP_FUNC_VIS            _LIBCPP_DLL_VIS
    __config(666,38):  note: expanded from macro '_LIBCPP_DLL_VIS'
    #  define _LIBCPP_DLL_VIS __declspec(dllimport)
    filesystem(1313,7):  note: previous attribute is here
    class _LIBCPP_EXCEPTION_ABI filesystem_error : public system_error {
    __config(675,37):  note: expanded from macro '_LIBCPP_EXCEPTION_ABI'
    #define _LIBCPP_EXCEPTION_ABI       _LIBCPP_DLL_VIS
    __config(666,38):  note: expanded from macro '_LIBCPP_DLL_VIS'
    #  define _LIBCPP_DLL_VIS __declspec(dllimport)

Differential Revision: https://reviews.llvm.org/D57354

llvm-svn: 352525
2019-01-29 18:48:35 +00:00
Eric Fiselier 011943a6e8 Fix PR40495 - is_invokable_v<void> does not compile
The meta-programming that attempted to form the invoke call expression
was not in a SFINAE context. This made it a hard error to provide
non-referencable types like 'void' or 'void (...) const'.

This patch fixes the error by checking the validity of the call
expression within a SFINAE context.

llvm-svn: 352522
2019-01-29 18:01:14 +00:00
Marshall Clow 5a8525e0b6 D14686: 'Protect against overloaded comma in random_shuffle and improve tests' I had to cut back on the tests with this, because they were not C++03 friendly. Thanks to gribozavr for the patch
llvm-svn: 352087
2019-01-24 19:20:19 +00:00
Marshall Clow 6973bb06d9 Change a couple of '&' to addressof(). NFC
llvm-svn: 352007
2019-01-24 02:02:50 +00:00
Marshall Clow 28166dd9b3 Apply D28248: 'Work around GCC PR37804'. Thanks to mdaniels for the patch
llvm-svn: 351993
2019-01-23 23:06:18 +00:00
Chandler Carruth 57b08b0944 Update more file headers across all of the LLVM projects in the monorepo
to reflect the new license. These used slightly different spellings that
defeated my regular expressions.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351648
2019-01-19 10:56:40 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Hans Wennborg 1fe469ae6c Bump the trunk version to 9.0.0svn
llvm-svn: 351320
2019-01-16 10:57:02 +00:00
Eric Fiselier 05019eb79f Fix feature test macros for atomics/mutexes without threading
llvm-svn: 351291
2019-01-16 02:10:28 +00:00
Eric Fiselier d01a4aa068 Fix PR40230 - std::pair may have padding on FreeBSD.
Summary:
FreeBSD ships a very old and deprecated ABI for std::pair where the copy and move constructors are not allowed to be trivial. D25389 change how this was implemented by introducing a non-trivial base class. This patch, introduced in October 2016, introduced an ABI bug that caused nested `std::pair` instantiations to have padding. For example:

```
using PairT = std::pair< std::pair<char, char>, char >;
static_assert(offsetof(PairT, first) == 0, "First member should exist at offset zero"); // Fails on FreeBSD!
```

The bug occurs because the base class for the first element (the nested pair) cannot be put at offset zero because the top-level pair already has the same base class laid out there.

This patch fixes that ABI bug by templating the dummy base class on the same parameters as the pair.

Technically this fix is an ABI break for users who depend on the "broken" ABI introduced in 2016. I'm putting this up for review so that the FreeBSD maintainers can sign off on fixing the ABI by breaking the ABI.
Another option, since we have to "break" the ABI to fix it, would be to move FreeBSD off the deprecated non-trivial pair ABI instead.

Also see:

* https://llvm.org/PR40230
* https://reviews.llvm.org/D21329



Reviewers: rsmith, dim, emaste

Reviewed By: rsmith

Subscribers: mclow.lists, krytarowski, christof, ldionne, libcxx-commits

Differential Revision: https://reviews.llvm.org/D56357

llvm-svn: 351290
2019-01-16 01:54:34 +00:00
Eric Fiselier d108bf85b0 Move internal usages of `alignof`/`__alignof` to use `_LIBCPP_ALIGNOF`.
Summary:
Starting in Clang 8.0 and GCC 8.0, `alignof` and `__alignof` return different values in same cases. Specifically `alignof` and `_Alignof` return the minimum alignment for a type, where as `__alignof` returns the preferred alignment. libc++ currently uses `__alignof` but means to use `alignof`. See  llvm.org/PR39713

This patch introduces the macro `_LIBCPP_ALIGNOF` so we can control which spelling gets used.

This patch does not introduce any ABI guard to provide the old behavior with newer compilers. However, if we decide that is needed, this patch makes it trivial to implement.

I think we should commit this change immediately, and decide what we want to do about the ABI afterwards. 

Reviewers: ldionne, EricWF

Reviewed By: ldionne, EricWF

Subscribers: jyknight, christof, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54814

llvm-svn: 351289
2019-01-16 01:51:12 +00:00
Eric Fiselier 32784a740a Implement feature test macros using a script.
Summary:
This patch implements all the feature test macros libc++ currently supports, as specified by the standard or cppreference prior to C++2a.

The tests and `<version>` header are generated using a script. The script contains a table of each feature test macro, the headers it should be accessible from, and its values of each dialect of C++.
When a new feature test macro is added or needed, the table should be updated and the script re-run.



Reviewers: mclow.lists, jfb, serge-sans-paille

Reviewed By: mclow.lists

Subscribers: arphaman, jfb, ldionne, libcxx-commits

Differential Revision: https://reviews.llvm.org/D56750

llvm-svn: 351286
2019-01-16 01:37:43 +00:00
Petr Hosek 2fefe153dd [libcxx] Mark do_open, do_get and do_close parameters unused when catopen is missing
When catopen is missing, do_open, do_get and do_close end up being
no-op, and as such their parameters will be unused which triggers a
warning/error when building with -Wunused-parameter.

Differential Revision: https://reviews.llvm.org/D56023

llvm-svn: 351027
2019-01-13 22:15:37 +00:00
Marshall Clow e495760140 Change from a to a . Fixes PR#39871.
llvm-svn: 350972
2019-01-11 21:57:12 +00:00
Adhemerval Zanella 63ea958521 [libcxx] Call __count_bool_true for bitset count
This patch aims to help clang with better information so it can inline
__bit_reference count function usage for both std::biset. Current clang
inliner can not infer that the passed typed will be used only to select
the optimized variant, it evaluates the type argument and type check as
a load plus compare (although later optimization phases correctly
optimized this out).

It is mainly to help llvm inliner to generate better code for std::bitset
count for aarch64. It helps on both runtime and code size, since if inline
decides that _VSTD::count should not be inlined the vectorization will
create both aligned and unaligned variants (which add both code size and
runtime costs)

llvm-svn: 350936
2019-01-11 17:31:17 +00:00
Marshall Clow 5c08881343 Implement the 'sys_time' portions of the C++20 calendaring stuff. Reviewed as D56494
llvm-svn: 350929
2019-01-11 15:12:04 +00:00
Louis Dionne 1d5f6a81f5 [libcxx] Reorganize tests since the application of P0602R4
Summary:
P0602R4 makes the special member functions of optional and variant
conditionally trivial based on the types in the optional/variant.
We already implemented that, but the tests were organized as if this
were a non-standard extension. This patch reorganizes the tests in a
way that makes more sense since this is not an extension anymore.

Reviewers: EricWF, mpark, mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54772

llvm-svn: 350884
2019-01-10 20:06:11 +00:00
Marshall Clow 8f9346922c Set the buffer of an fstream to empty when the underlying file is closed. This 'fixes' PR#38052 - std::fstream still good after closing and updating content.
llvm-svn: 350603
2019-01-08 02:48:45 +00:00
Volodymyr Sapsai fb0e1908d4 [libcxx] Optimize vectors construction of trivial types from an iterator range with const-ness mismatch.
We already have a specialization that will use memcpy for construction
of trivial types from an iterator range like

    std::vector<int>(int *, int *);

But if we have const-ness mismatch like

    std::vector<int>(const int *, const int *);

we would use a slow path that copies each element individually. This change
enables the optimal specialization for const-ness mismatch. Fixes PR37574.

Contributions to the patch are made by Arthur O'Dwyer, Louis Dionne.

rdar://problem/40485845

Reviewers: mclow.lists, EricWF, ldionne, scanon

Reviewed By: ldionne

Subscribers: christof, ldionne, howard.hinnant, cfe-commits

Differential Revision: https://reviews.llvm.org/D48342

llvm-svn: 350583
2019-01-08 00:03:16 +00:00
Eric Fiselier b168a7c660 Fix PR39749 - Headers containing just #error harm __has_include.
This patch changes <experimental/foo> to use #warning instead of
is harmful to common feature detection idioms.

We should also consider only emitting the warning when __DEPRECATED is
defined, like we do in the <ext/foo> headers. Users may want to specify
"-Werror=-W#warnings" while still ignoring the libc++ warnings.

llvm-svn: 350485
2019-01-06 00:37:31 +00:00
Louis Dionne 9f3561c292 [libcxx] Remove unused macro _LIBCPP_HAS_UNIQUE_TYPEINFO
Summary:
We already have the negation of that as _LIBCPP_HAS_NONUNIQUE_TYPEINFO.
Having both defined is confusing, since only one of them is used.

Reviewers: EricWF, mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54537

llvm-svn: 349947
2018-12-21 20:14:43 +00:00
Louis Dionne 5517aa6172 [NFC] Fix typo in comment
llvm-svn: 349932
2018-12-21 17:32:23 +00:00
Eric Fiselier 8c0c8e154b Don't forward declare _FilesystemClock in C++03
llvm-svn: 349887
2018-12-21 04:30:04 +00:00
Eric Fiselier 49b183a9ec Implement LWG 3065: Make path operators friends.
This prevents things like:

using namespace std::filesystem;
auto x = L"a/b" == std::string("a/b");

llvm-svn: 349884
2018-12-21 04:09:01 +00:00
Eric Fiselier 866885e12a Implement LWG 3145: file_clock breaks ABI for C++17 implementations.
This patch adds std::chrono::file_clock, but without breaking the
existing ABI for std::filesystem.

llvm-svn: 349883
2018-12-21 03:54:57 +00:00
Volodymyr Sapsai e7652f5c0d [libcxx] Use custom allocator's `construct` in C++03 when available.
Makes libc++ behavior consistent between C++03 and C++11.

Can use `decltype` in C++03 because `include/__config` defines a macro when
`decltype` is not available.

Reviewers: mclow.lists, EricWF, erik.pilkington, ldionne

Reviewed By: ldionne

Subscribers: dexonsmith, cfe-commits, howard.hinnant, ldionne, christof, jkorous, Quuxplusone

Differential Revision: https://reviews.llvm.org/D48753

llvm-svn: 349676
2018-12-19 20:08:43 +00:00
Louis Dionne c8ca4d8cc1 [libcxx][NFC] Properly indent nested #ifdefs and #defines
I just realized I had always been reading this wrong because of the lack
of indentation, so I'm re-indenting this properly.

llvm-svn: 349408
2018-12-17 22:22:44 +00:00
Louis Dionne 04695a7539 [libcxx] Speeding up partition_point/lower_bound/upper_bound
This is a re-application of r345525, which had been reverted by fear of
a regression.

Reviewed as https://reviews.llvm.org/D53994.
Thanks to Denis Yaroshevskiy for the patch.

llvm-svn: 349358
2018-12-17 16:04:39 +00:00
Michal Gorny a25cd0c2da [regex] Use distinct __regex_word on NetBSD
NetBSD defines character classes up to 0x2000.  Use 0x8000 as a safe
__regex_word that hopefully will not collide with other values
in the foreseeable future.

Differential Revision: https://reviews.llvm.org/D55657

llvm-svn: 349293
2018-12-16 09:18:26 +00:00
Marshall Clow cac3d118ae When resolving a merge conflict, I put something inside an #ifdef. Fixed.
llvm-svn: 349181
2018-12-14 19:25:22 +00:00
Marshall Clow f60c63c090 Implement P1209 - Adopt Consistent Container Erasure from Library Fundamentals 2 for C++20. Reviewed as https://reviews.llvm.org/D55532
llvm-svn: 349178
2018-12-14 18:49:35 +00:00
Thomas Anderson 1cffc38485 [libc++] Fix _LIBCPP_EXPORTED_FROM_ABI when visibility annotations are disabled
Fixes a bug where functions would get exported when building with
-fvisibility=hidden and defining _LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS. No
visibility annotations should be added in this case.

The new logic for _LIBCPP_EXPORTED_FROM_ABI matches that of the other visibility
annotations around it.

Differential Revision: https://reviews.llvm.org/D55664

llvm-svn: 349080
2018-12-13 20:06:14 +00:00
Louis Dionne 589f1764fc [libcxx] Add assertion in deque::pop_back when popping from an empty deque
Also, add tests making sure that vector and deque both catch the problem
when assertions are enabled. Otherwise, deque would segfault and vector
would never terminate.

llvm-svn: 348994
2018-12-12 23:58:25 +00:00
Louis Dionne 9f77b1a1de [pair] Mark constructors as conditionally noexcept
Summary:
std::tuple marks its constructors as noexcept when the corresponding
memberwise constructors are noexcept too -- this commit improves std::pair
so that it behaves the same.

This is a re-application of r348824, which broke the build in C++03 mode
because a test was marked as supported in C++03 when it shouldn't be.

Note:
I did not add support in the explicit and non-explicit `pair(_Tuple&& __p)`
constructors because those are non-standard extensions, and supporting them
properly is tedious (we have to copy the rvalue-referenceness of the deduced
_Tuple&& onto the result of tuple_element).

<rdar://problem/29537079>

Reviewers: mclow.lists, EricWF

Subscribers: christof, llvm-commits

Differential Revision: https://reviews.llvm.org/D48669

llvm-svn: 348847
2018-12-11 14:22:28 +00:00
Marshall Clow 7dad0bd68b Second part of P0482 - char8_t. Reviewed as https://reviews.llvm.org/D55308
llvm-svn: 348828
2018-12-11 04:35:44 +00:00
Louis Dionne d5a20703c4 Revert "[pair] Mark constructors as conditionally noexcept"
This broke the tests on Linux. Reverting until I find out why the tests
are broken (tomorrow).

llvm-svn: 348825
2018-12-11 02:32:46 +00:00
Louis Dionne 76cce3b2bd [pair] Mark constructors as conditionally noexcept
Summary:
std::tuple marks its constructors as noexcept when the corresponding
memberwise constructors are noexcept too -- this commit improves std::pair
so that it behaves the same.

Note:
I did not add support in the explicit and non-explicit `pair(_Tuple&& __p)`
constructors because those are non-standard extensions, and supporting them
properly is tedious (we have to copy the rvalue-referenceness of the deduced
_Tuple&& onto the result of tuple_element).

<rdar://problem/29537079>

Reviewers: mclow.lists, EricWF

Subscribers: christof, llvm-commits

Differential Revision: https://reviews.llvm.org/D48669

llvm-svn: 348824
2018-12-11 02:17:23 +00:00
Eric Fiselier 08e231dd9c Add a version of std::function that includes a few optimizations in ABI V2.
Patch by Jordan Soyke (jsoyke@google.com)
Reviewed as D55045

The result of running the benchmarks and comparing them can be found
here: https://gist.github.com/EricWF/a77fd42ec87fc98da8039e26d0349498

llvm-svn: 348812
2018-12-11 00:14:34 +00:00
Eric Fiselier 5f503b47cb Refactor std::function to more easily support alternative implementations.
Patch from Jordan Soyke (jsoyke@google.com)
Reviewed as D55520

This change adds a new internal class, called __value_func, that adds
a minimal subset of value-type semantics to the internal __func interface.

The change is NFC, and is cleanup for the upcoming ABI v2 function implementation (D55045).

llvm-svn: 348778
2018-12-10 18:14:09 +00:00
Louis Dionne 036a9a0420 [libcxx] Add paranoid cast-to-void in comma operator
llvm-svn: 348611
2018-12-07 16:42:28 +00:00
Louis Dionne 3560fbf304 [libc++] Improve diagnostics for non-const comparators and hashers in associative containers
Summary:
When providing a non-const-callable comparator in a map or set, the
warning diagnostic does not include the point of instantiation of
the container that triggered the warning, which makes it difficult
to track down the problem. This commit improves the diagnostic by
placing it directly in the body of the associative container.

The same change is applied to unordered associative containers, which
had a similar problem.

Finally, this commit cleans up the forward declarations of several
map and unordered_map helpers, which are not needed anymore.

<rdar://problem/41370747>

Reviewers: EricWF, mclow.lists

Subscribers: christof, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D48955

llvm-svn: 348529
2018-12-06 21:46:17 +00:00
Louis Dionne f7f5a1f778 [libcxx] Don't depend on availability markup to provide the streams in the dylib
Whether an explicit instantiation declaration should be provided is not
a matter of availability markup.

This problem is exemplified by the fact that some tests were incorrectly
marked as XFAIL when they should instead have been using the definition
of streams from the headers, and hence passing, and that, regardless of
whether visibility annotations are enabled.

llvm-svn: 348436
2018-12-06 00:24:58 +00:00
Louis Dionne bb9ca6d0bf [libcxx] Implement P0318: unwrap_ref_decay and unwrap_reference
Summary:
This was voted into C++20 in San Diego. Note that there was a revision
D0318R2 which did include unwrap_reference_t, but we mistakingly voted
P0318R1 into the C++20 Working Draft (which does not include
unwrap_reference_t). This patch implements D0318R2, which is what
we'll end up with in the Working Draft once this mistake has been
fixed.

Reviewers: EricWF, mclow.lists

Subscribers: christof, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54485

llvm-svn: 348138
2018-12-03 14:03:27 +00:00
Marshall Clow 08794627a3 First part of P0482 - Establish that char8_t is an integral type, and that numeric_limits<char8_t> is valid and sane. (second try)
llvm-svn: 347930
2018-11-29 23:21:18 +00:00
Marshall Clow 80fabab677 Revert commit r347904 because it broke older compilers
llvm-svn: 347908
2018-11-29 20:04:47 +00:00
Marshall Clow 8143278500 First part of P0482 - Establish that char8_t is an integral type, and that numeric_limits<char8_t> is valid and sane.
llvm-svn: 347904
2018-11-29 19:49:48 +00:00
Louis Dionne e823b6d7e6 [libcxx] Remove bad_array_length
Summary:
std::bad_array_length was added by n3467, but this never made it into C++.
This commit removes the definition of std::bad_array_length from the headers
AND from the shared library. See the comments in the ABI changelog for details
about the ABI implications of this change.

Reviewers: mclow.lists, dexonsmith, howard.hinnant, EricWF

Subscribers: christof, jkorous, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54804

llvm-svn: 347903
2018-11-29 19:44:57 +00:00
Eric Fiselier 9d25ada420 Revert "Move internal usages of `alignof`/`__alignof` to use `_LIBCPP_ALIGNOF`. "
This reverts commit 087f065cb0c7463f521a62599884493aaee2ea12.

The tests were failing on 32 bit builds, and I don't have time
to clean them up right now. I'll recommit tomorrow with fixed tests.

llvm-svn: 347816
2018-11-28 22:24:19 +00:00
Marshall Clow 4d64d7dd64 Implement P0966 - string::reserve should not shrink
llvm-svn: 347789
2018-11-28 18:18:34 +00:00
Eric Fiselier 8a486dac25 Move internal usages of `alignof`/`__alignof` to use `_LIBCPP_ALIGNOF`.
Summary:
Starting in Clang 8.0 and GCC 8.0, `alignof` and `__alignof` return different values in same cases. Specifically `alignof` and `_Alignof` return the minimum alignment for a type, where as `__alignof` returns the preferred alignment. libc++ currently uses `__alignof` but means to use `alignof`. See  llvm.org/PR39713

This patch introduces the macro `_LIBCPP_ALIGNOF` so we can control which spelling gets used.

This patch does not introduce any ABI guard to provide the old behavior with newer compilers. However, if we decide that is needed, this patch makes it trivial to implement.

I think we should commit this change immediately, and decide what we want to do about the ABI afterwards. 

Reviewers: ldionne, EricWF

Reviewed By: EricWF

Subscribers: christof, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54814

llvm-svn: 347787
2018-11-28 18:16:02 +00:00
Louis Dionne 9a494eacba [libcxx] Remove dynarray
Summary:
std::dynarray had been proposed for C++14, but it was pulled out from C++14
and there are no plans to standardize it anymore.

Reviewers: mclow.lists, EricWF

Subscribers: mgorny, christof, jkorous, dexonsmith, arphaman, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54801

llvm-svn: 347783
2018-11-28 18:02:00 +00:00
Louis Dionne a86710f1e8 [libcxx] Apply _LIBCPP_INLINE_VISIBILITY for std::hash for string_view
llvm-svn: 347765
2018-11-28 15:22:30 +00:00
Marshall Clow 44d247d280 Implement P1085R2 - Should Span be Regular?. This consists entirely of deletions
llvm-svn: 347672
2018-11-27 16:35:41 +00:00
Eric Fiselier e051f98d09 Remove duplicate _LIBCPP_INLINE_VISIBILITY attributes.
This attribute should appear only on the first declaration. This
patch cleans up <string> by removing the attribute on redeclarations.

llvm-svn: 347608
2018-11-26 22:51:35 +00:00
Eric Fiselier 01a87ef88b Add basic_string::__resize_default_init (from P1072)
This patch adds an implementation of __resize_default_init as
described in P1072R2. Additionally, it uses it in filesystem to
demonstrate its intended utility.

Once P1072 lands, or if it changes it's interface, I will adjust
the internal libc++ implementation to match.

llvm-svn: 347589
2018-11-26 20:15:38 +00:00
Louis Dionne 2804508ffe [libcxx] Remove unused definition of aligned allocation macro on old OS X
We don't support mac OS 10.6 and older anymore, so this macro can never
be defined. This bit of code had been added in D28931 as a fix for
PR31448, but it doesn't seem necessary anymore.

llvm-svn: 347427
2018-11-21 21:22:08 +00:00
Louis Dionne 53922b7dd1 [libcxx] Make sure operator+ is declared with the right visibility attribute
Otherwise, Clang complains about internal_linkage not being applied to the
first declaration of the operator (and rightfully so).

llvm-svn: 347400
2018-11-21 17:31:55 +00:00
Louis Dionne 352adb6532 [libcxx] Mark stray symbols as hidden to try and fix the build
r347395 changed the ABI list on Linux, but two of those symbols are still
being exported from the shared object:

    _ZSt18make_exception_ptrINSt3__112future_errorEESt13exception_ptrT_
    _ZNSt3__1plIcNS_11char_traitsIcEENS_9allocatorIcEEEENS_12basic_stringIT_T0_T1_EERKS9_PKS6_

This commit makes sure those symbols are not exported, as they should be.

llvm-svn: 347399
2018-11-21 17:00:52 +00:00
Louis Dionne 835140a427 [libcxx] Make sure we can build with -fvisibility=hidden on Linux
Summary:
This commit marks a few functions as hidden and removes them from the ABI list
on Linux such that libc++ can be built with -fvisibility=hidden. The functions
marked as hidden by this patch were exported from the shared object only
because they were implicitly instantiated function templates. It is safe
to stop exporting those symbols from the shared object because nobody could
actually depend on them: implicit instantiations are not taken from shared
objects.

The symbols removed in this commit are basically the same that had been
removed in https://reviews.llvm.org/D53868, but that patch had to be reverted
because it broke the build (because the functions were not marked as hidden
like this patch does).

Reviewers: EricWF, mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54639

llvm-svn: 347395
2018-11-21 16:24:46 +00:00
Zhihao Yuan 147b25b4a1 [libc++] Implement P0487R1 - Fixing operator>>(basic_istream&, CharT*)
Summary:
Avoid buffer overflow by replacing the pointer interface with an array reference interface in C++2a.
Tentatively ready on Batavia2018.

 https://wg21.link/lwg2499
 https://wg21.link/p0487

Reviewers: mclow.lists, ldionne, EricWF

Reviewed By: ldionne

Subscribers: libcxx-commits, cfe-commits, christof

Differential Revision: https://reviews.llvm.org/D51268

llvm-svn: 347377
2018-11-21 03:30:10 +00:00
Louis Dionne 8eb65cb25e [NFC] Reformat availability #defines in __config
Aligning everything makes what we're doing more obvious.

llvm-svn: 347363
2018-11-20 23:18:25 +00:00
Louis Dionne c2b375ad60 [libcxx] Fix threads detection on GNU/Hurd
GNU/Hurd provides standard Posix threads

Reviewed as https://reviews.llvm.org/D54339.
Thanks to Samuel Thibault for the patch.

llvm-svn: 347347
2018-11-20 21:14:05 +00:00
Louis Dionne 8a063df194 [libcxx] Add availability markup for bad_optional_access, bad_variant_access and bad_any_cast
Reviewers: dexonsmith, EricWF

Subscribers: christof, arphaman, libcxx-commits

Differential Revision: https://reviews.llvm.org/D53256

llvm-svn: 347219
2018-11-19 15:37:04 +00:00
Marshall Clow cf355fc373 Implement P0972R0: <chrono> zero(), min(), and max() should be noexcept. Reviewed as https://reviews.llvm.org/D53828
llvm-svn: 346766
2018-11-13 17:22:41 +00:00
Louis Dionne 7272026993 [libcxx] Implement http://wg21.link/p1006, constexpr in pointer_traits
Summary:
P1006 adds support for constexpr in the specialization of pointer_traits
for raw pointers. This is necessary in order to use pointer_traits in
the upcoming constexpr containers. We expect P1006 to be voted into the
working draft for C++20 at the San Diego meeting.

Reviewers: mclow.lists, EricWF

Subscribers: christof, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D53867

llvm-svn: 346764
2018-11-13 17:04:05 +00:00
Marshall Clow d4fa0381e3 Fix PR39619 - iterator_traits isn't SFINAE-friendly enough. Thanks to Eric for the report
llvm-svn: 346738
2018-11-13 05:33:31 +00:00
Louis Dionne d9247890da [NFC] Fix typo in <tuple>
llvm-svn: 346629
2018-11-12 01:28:07 +00:00
Petr Hosek f30c0117c8 [libcxx] Provide thread annotations for shared_mutex
shared_mutex was introduced in C++17 but its implementation currently
doesn't use Clang's thread annotations like regular mutex. This change
adds those.

Differential Revision: https://reviews.llvm.org/D54290

llvm-svn: 346567
2018-11-09 23:32:25 +00:00
Fangrui Song 892bbd3f88 Fix -Wimplicit-fallthrough warning
Reviewers: EricWF, ldionne, mclow.lists

Reviewed By: ldionne

Subscribers: christof, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54234

llvm-svn: 346369
2018-11-07 23:51:13 +00:00
Louis Dionne d1ad7b31ee [NFC] Fix incorrect comment in std::list
llvm-svn: 346072
2018-11-03 17:51:09 +00:00
Louis Dionne e0a724ef9c Revert "Bug 39129: Speeding up partition_point/lower_bound/upper_bound/ by using unsigned division by 2 when possible."
This reverts r345525. I'm reverting because that patch apparently caused
a regression on certain platforms (see https://reviews.llvm.org/D53994).
Since we don't fully understand the reasons for the regression, I'm
reverting until we can provide a fix we understand.

llvm-svn: 345893
2018-11-01 21:24:32 +00:00
Reid Kleckner 60cce5c782 Use C++11 fallthrough attribute syntax when available and add a break
Summary:
This silences the two -Wimplicit-fallthrough warnings clang finds in
ItaniumDemangle.h in libc++abi.

Clang does not have a GNU attribute spelling for this attribute, so this
is necessary.

I will commit the same change to the LLVM demangler soon.

Reviewers: EricWF, ldionne

Subscribers: christof, erik.pilkington, cfe-commits

Differential Revision: https://reviews.llvm.org/D53985

llvm-svn: 345870
2018-11-01 18:24:03 +00:00
Louis Dionne 8df1d5a546 [libcxx] Fix usage of _C2, which is a "nasty macro" in some environments
The problem was pointed out in https://reviews.llvm.org/D48896#inline-475775.

llvm-svn: 345834
2018-11-01 14:41:37 +00:00
Erik Pilkington 5c4e07ae5c Second half of C++17's splicing maps and sets
This commit adds a merge member function to all the map and set containers,
which splices nodes from the source container. This completes support for
P0083r3.

Differential revision: https://reviews.llvm.org/D48896

llvm-svn: 345744
2018-10-31 17:31:35 +00:00
Eric Fiselier fe13c13cc2 Make libc++'s versioning namespace customizable
Summary:
This patch makes the versioning namespace libc++ uses customizable by the user using `-DLIBCXX_ABI_NAMESPACE=__foo`. 

This allows users to build custom versions of libc++ which can be linked into binaries with other libc++ versions without causing symbol conflicts or ODR issues. 

Reviewers: mclow.lists, ldionne

Reviewed By: ldionne

Subscribers: kristina, smeenai, mgorny, phosek, libcxx-commits

Differential Revision: https://reviews.llvm.org/D53879

llvm-svn: 345657
2018-10-30 21:44:53 +00:00
Eric Fiselier 2f3e8b3d2e Unify definition of _LIBCPP_BEGIN/END_NAMESPACE_STD
llvm-svn: 345561
2018-10-30 02:02:00 +00:00
Eric Fiselier 8c40d81d4f Bug 39129: Speeding up partition_point/lower_bound/upper_bound/ by using unsigned division by 2 when possible.
Patch by Denis Yaroshevskiy (denis.yaroshevskij@gmail.com)

The rational and measurements can be found in the bug description: https://bugs.llvm.org/show_bug.cgi?id=39129

Reviewed as https://reviews.llvm.org/D52697

llvm-svn: 345525
2018-10-29 19:25:02 +00:00
Louis Dionne e9d85264ac [libc++] Use exclude_from_explicit_instantiation instead of always_inline
Summary:
This commit adopts the exclude_from_explicit_instantiation attribute discussed
at [1] and reviewed in [2] in libc++ to supplant the use of __always_inline__
for visibility purposes.

This change means that users wanting to link together translation units built
with different versions of libc++'s headers into the same final linked image
MUST define the _LIBCPP_HIDE_FROM_ABI_PER_TU macro to 1 when building those
TUs. Doing otherwise will lead to ODR violations and ABI issues.

[1]: http://lists.llvm.org/pipermail/cfe-dev/2018-August/059024.html
[2]: https://reviews.llvm.org/D51789

Reviewers: rsmith, EricWF

Subscribers: dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D52405

llvm-svn: 345516
2018-10-29 17:30:04 +00:00
Eric Fiselier e503a1c3b8 Fix PR39458 _LIBCPP_DEBUG breaks heterogeneous compare.
The types/comparators passed to std::upper_bound and std::lower_bound
are not required to provided to provide an operator</comp(...) which
accepts the arguments in reverse order. Nor are the ranges required
to have a strict weak ordering.

However, in debug mode we attempted to check the result of a comparison
with the arguments reversed, which may not compiler.

This patch removes the use of the debug comparator for upper_bound
and lower_bound.

equal_range et al still use debug comparators when they call
__upper_bound and __lower_bound.

See llvm.org/PR39458

llvm-svn: 345434
2018-10-26 22:54:46 +00:00
Eric Fiselier 43245b1f3b Fix incorrect use of aligned allocation in get_temporary_buffer.
llvm-svn: 345403
2018-10-26 17:12:32 +00:00
Marshall Clow 27e9fdb2ff Run the min/max tests agaist the header <charconv>. Fix that header so it passes. NFC.
llvm-svn: 345352
2018-10-26 01:00:56 +00:00
Eric Fiselier 8622e866a6 fix incorrect placement of _LIBCPP_ALWAYS_INLINE in valarray
llvm-svn: 345289
2018-10-25 17:43:26 +00:00
Eric Fiselier f25b75b91b Implement sized deallocation for std::allocator and friends.
Summary:
C++14 sized deallocation is disabled by default due to ABI concerns. However, when a user manually enables it then libc++ should take advantage of it since sized deallocation can provide a significant performance win depending on the underlying malloc implementation. (Note that libc++'s definitions of sized delete don't do anything special yet, but users are free to provide their own).

This patch updates __libcpp_deallocate to selectively call sized operator delete when it's available. `__libcpp_deallocate_unsized` should be used when the size of the allocation is unknown.

On Apple this patch makes no attempt to determine if the sized operator delete is unavailable, only that the language feature is enabled. This could cause a compile error when using `std::allocator`, but the same compile error would occur whenever the user calls `new`, so I don't think it's a problem.

Reviewers: ldionne, mclow.lists

Reviewed By: ldionne

Subscribers: rsmith, ckennelly, libcxx-commits, christof

Differential Revision: https://reviews.llvm.org/D53120

llvm-svn: 345281
2018-10-25 17:21:30 +00:00
Louis Dionne 9b3222f613 [libc++] Make sure we can build libc++ with -fvisibility=hidden
Summary:
When building with -fvisibility=hidden, some symbols do not get exported from
libc++.dylib. This means that some entities are not explicitly given default
visibility in the source code, and that we rely on the fact -fvisibility=default
is the default. This commit explicitly gives default visibility to those
symbols to avoid being dependent on the command line flags used.

The commit also remove symbols from the dylib -- those symbols do not
actually need to be exported from the dylib and this should not be an
ABI break.

Finally, in the future, we may want to mark the whole std:: namespace as
having hidden visibility (to switch from opt-out to opt-in), in which
case the changes done in this commit will be required.

Reviewers: EricWF

Subscribers: mgorny, christof, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D52662

llvm-svn: 345260
2018-10-25 12:13:43 +00:00
Eric Christopher 9ecdb5a711 Revert "Fix use of __libcpp_deallocate in dynarray"
This reverts commit r345234 as it depended on the sized deallocation commit.

llvm-svn: 345240
2018-10-25 06:43:56 +00:00
Eric Christopher 9bbee38db3 Temporarily Revert "Implement sized deallocation for std::allocator and friends."
This is breaking the bots here (and related): http://lab.llvm.org:8011/builders/libcxx-libcxxabi-x86_64-linux-ubuntu-asan/builds/1428

This reverts commit r345214.

llvm-svn: 345239
2018-10-25 06:20:12 +00:00
Eric Fiselier 46493ac9b5 Fix use of __libcpp_deallocate in dynarray
llvm-svn: 345234
2018-10-25 02:36:31 +00:00
Eric Fiselier 7e6448bb02 Implement sized deallocation for std::allocator and friends.
Summary:
C++14 sized deallocation is disabled by default due to ABI concerns. However, when a user manually enables it then libc++ should take advantage of it since sized deallocation can provide a significant performance win depending on the underlying malloc implementation. (Note that libc++'s definitions of sized delete don't do anything special yet, but users are free to provide their own).

This patch updates __libcpp_deallocate to selectively call sized operator delete when it's available. `__libcpp_deallocate_unsized` should be used when the size of the allocation is unknown.

On Apple this patch makes no attempt to determine if the sized operator delete is unavailable, only that the language feature is enabled. This could cause a compile error when using `std::allocator`, but the same compile error would occur whenever the user calls `new`, so I don't think it's a problem.

Reviewers: ldionne, mclow.lists

Reviewed By: ldionne

Subscribers: rsmith, ckennelly, libcxx-commits, christof

Differential Revision: https://reviews.llvm.org/D53120

llvm-svn: 345214
2018-10-24 22:44:01 +00:00
Petr Hosek 76ccec07b4 Revert "Teach __libcpp_is_floating_point that __fp16 and _Float16 are"
This reverts commits r333103 and r333108. _Float16 and __fp16 are C11
extensions and compilers other than Clang don't define these for C++.

Differential Revision: https://reviews.llvm.org/D53670

llvm-svn: 345199
2018-10-24 21:29:15 +00:00
Marshall Clow 5ac28a0cfd Off-by-one errors strike again. Thank goodness for ASAN and the bots.
llvm-svn: 345076
2018-10-23 20:07:45 +00:00
Marshall Clow 55fb053f57 When filling a vector<bool> with stuff, initialize the last word of the storage that you're touching. Otherwise, when we lay down the bits with operator&=, we get UB from reading uninitialized memory. Fixes Bug 39354. Thanks to David Wagner for the bug report.
llvm-svn: 345067
2018-10-23 18:38:15 +00:00
Marshall Clow 2d7bde547f Update commnents to reflect the changes for LWG#3127. NFC
llvm-svn: 344953
2018-10-22 20:50:06 +00:00
Marshall Clow 05fe329687 Update commnents to reflect the changes for LWG#3122. NFC
llvm-svn: 344950
2018-10-22 20:44:37 +00:00
Louis Dionne 4084df0040 [libcxx] Avoid repeating the definition of std:: namespaces
This reduces code duplication a tiny bit.

llvm-svn: 344642
2018-10-16 20:02:59 +00:00
Louis Dionne 7833b88ad8 [libcxx] Remove _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY
That macro has been defined to _LIBCPP_HIDE_FROM_ABI_AFTER_V1 for many
weeks now, so we're actually replacing uses of it for uses of
_LIBCPP_HIDE_FROM_ABI_AFTER_V1 directly.

This should not change or break anything since the two macros are
100% equivalent, unless somebody is (incorrectly!) relying on
_LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY being defined.

llvm-svn: 344641
2018-10-16 19:26:23 +00:00
Marshall Clow 5b08c1742a Recommit <chrono> changes with a couple xtra tests marked to fail on apple's clang. Reviewed as D51762
llvm-svn: 344627
2018-10-16 17:27:54 +00:00
Marshall Clow 69067f2bfd Partial fix for PR38964. (<string> can't be built with gcc -std=c++03) Reviewed as https://reviews.llvm.org/D52240
llvm-svn: 344616
2018-10-16 16:02:18 +00:00
Artem Dergachev a9bc0face5 Revert r344529 "Implement the first part of the calendar support for C++20"
Revert r344535 "Wrap up the new chrono literals in an #ifdef..."
Revert r344546 "Mark a couple of test cases as 'C++17-only'..."

Some of the buildbot failures were masked by another error,
and this one was probably missed.

llvm-svn: 344580
2018-10-16 02:40:42 +00:00
Marshall Clow 323e01d46f Wrap up the new chrono literals in an #ifdef so that old versions of clang don't complain. I'm looking at you, clang 5.0.1
llvm-svn: 344535
2018-10-15 17:33:20 +00:00
Marshall Clow 06ba9f5246 Implement the first part of the calendar support for C++20. This is still incomplete; there will be more patches coming. Reviewed as D51762
llvm-svn: 344529
2018-10-15 16:06:37 +00:00
Marshall Clow c83d283a2e Revert commit r344254; does not work with C++03
llvm-svn: 344261
2018-10-11 17:28:57 +00:00
Marshall Clow e98be18311 Prefer to use the __is_XXX compiler intrinsics to the (old, busted) __has_XXX intrinsics when implementing type traits. Thanks to Richard Smith for the patch.
llvm-svn: 344254
2018-10-11 15:38:07 +00:00
Eric Fiselier 33e402ae2b Fix use of removed _LIBCPP_HAS_NO_BUILTIN_ALIGNED_OPERATOR_NEW_DELETE
It was replaced with the better named
_LIBCPP_HAS_NO_BUILTIN_OVERLOADED_OPERATOR_NEW_DELETE.

llvm-svn: 344214
2018-10-11 01:48:00 +00:00
Eric Fiselier 42f9868cd8 Distinguish between library and language support for aligned allocation.
There are two cases:
1. The library has all it needs to provide align_val_t and the
new/delete overloads needed to support aligned allocation.
2. The compiler has actually turned the language feature on.

There are times where libc++ needs to distinguish between the two.

This patch adds the additional macro
_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION which denotes when case (1)
does not hold. _LIBCPP_HAS_NO_ALIGNED_ALLOCATION is defined whenever
_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION is defined, or when the
compiler has not enabled the language feature.

Additionally this patch cleans up a number of other macros related
to detection of aligned allocation machinery.

llvm-svn: 344207
2018-10-11 00:17:24 +00:00
Aaron Puchert 7f208f02db Annotate scoped_lock as with scoped_lockable attribute
Summary:
Scoped capabilities need to be annotated as such, otherwise the thread
safety analysis won't work as intended.

Fixes PR39234.

Reviewers: ldionne

Reviewed By: ldionne

Subscribers: christof, libcxx-commits

Differential Revision: https://reviews.llvm.org/D53049

llvm-svn: 344096
2018-10-09 23:42:29 +00:00
Marshall Clow 2dd5335204 Do the math in uniform_int_distribution::operator() as unsigned to prevent UB when overflowing. Also add a UBSAN notification that we're ffine with unsigned overflow. This fixes PR#32617. Thanks to Vincent & Christoph for their help with this issue.
llvm-svn: 343996
2018-10-08 20:20:34 +00:00
Louis Dionne 98faa3976d [libc++][NFC] Add error messages to a couple of static_asserts in span
Summary:
Add error messages to a couple of static_asserts in span to match the
style used in the rest of the file. Also fix an extra paren typo in a
assert error message.

Committed on behalf of Jason Lovett.

Reviewers: ldionne

Subscribers: libcxx-commits

Differential Revision: https://reviews.llvm.org/D52841

llvm-svn: 343725
2018-10-03 21:36:16 +00:00
Eric Fiselier b6f4d445f0 Attempt to fix aligned allocation configuration under clang-cl
When we're using clang-cl and Microsoft's runtime implementation,
we don't provide align_val_t or aligned new/delete ourselves.

This patch updates the _LIBCPP_HAS_NO_ALIGNED_ALLOCATION macro
to reflect this.

llvm-svn: 343441
2018-10-01 04:08:06 +00:00
Eric Fiselier a0e23576b8 Fix Shadowing warning on Windows
llvm-svn: 343439
2018-10-01 02:54:08 +00:00
Eric Fiselier 0b485f3e91 Fix even more Clang warnings.
This patch disables shift-sign-overflow warnings for now. It also
fixes most -Wfloat-equal warnings and -Wextra-semi warnings.

llvm-svn: 343438
2018-10-01 01:59:37 +00:00
Louis Dionne f9a52903ef [libc++] Remove Fuchsia-specific knowledge to pick the ABI version
Summary:
The ABI version used by libc++ is a configuration option just like any other
configuration option. It is a knob that can be used by vendors to customize
the libc++ that they ship. As such, we should not be hardcoding vendor-specific
configuration choices in libc++.

When building libc++ for Fuchsia, Fuchsia's build scripts should simply define
the libc++ ABI version to 2 -- this will result in the _LIBCPP_ABI_VERSION
macro being defined in the __config header that is generated when libc++ is
built and installed, which is the correct way to customize libc++'s behavior
for specific vendors.

Reviewers: phosek, EricWF

Subscribers: mgorny, christof, dexonsmith, cfe-commits, libcxx-commits

Differential Revision: https://reviews.llvm.org/D52397

llvm-svn: 343079
2018-09-26 08:24:51 +00:00
Louis Dionne ea5cd3b476 [libc++] Add deprecated attributes to many deprecated components
Summary:
These deprecation warnings are opt-in: they are only enabled when the
_LIBCXX_DEPRECATION_WARNINGS macro is defined, which is not the case
by default. Note that this is a first step in the right direction, but
I wasn't able to get an exhaustive list of all deprecated components
per standard, so there's certainly stuff that's missing. The list of
components this commit marks as deprecated is:

in C++11:
- auto_ptr, auto_ptr_ref
- binder1st, binder2nd, bind1st(), bind2nd()
- pointer_to_unary_function, pointer_to_binary_function, ptr_fun()
- mem_fun_t, mem_fun1_t, const_mem_fun_t, const_mem_fun1_t, mem_fun()
- mem_fun_ref_t, mem_fun1_ref_t, const_mem_fun_ref_t, const_mem_fun1_ref_t, mem_fun_ref()

in C++14:
- random_shuffle()

in C++17:
- unary_negate, binary_negate, not1(), not2()

<rdar://problem/18168350>

Reviewers: mclow.lists, EricWF

Subscribers: christof, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D48912

llvm-svn: 342843
2018-09-23 18:35:00 +00:00
Louis Dionne 0805a4fa9c [NFC][libcxx] Rename helpers with 4 underscores to something more reasonable
llvm-svn: 342840
2018-09-23 16:44:50 +00:00
Roman Lebedev c65d39a464 [libc++] Add _LIBCPP_ENABLE_NODISCARD and _LIBCPP_NODISCARD_EXT to allow pre-C++2a [[nodiscard]]
Summary:
The `[[nodiscard]]` attribute is intended to help users find bugs where
function return values are ignored when they shouldn't be. After C++17 the
C++ standard has started to declared such library functions as `[[nodiscard]]`.
However, this application is limited and applies only to dialects after C++17.
Users who want help diagnosing misuses of STL functions may desire a more
liberal application of `[[nodiscard]]`.

For this reason libc++ provides an extension that does just that! The
extension must be enabled by defining `_LIBCPP_ENABLE_NODISCARD`. The extended
applications of `[[nodiscard]]` takes two forms:

1. Backporting `[[nodiscard]]` to entities declared as such by the
   standard in newer dialects, but not in the present one.

2. Extended applications of `[[nodiscard]]`, at the libraries discretion,
   applied to entities never declared as such by the standard.

Users may also opt-out of additional applications `[[nodiscard]]` using
additional macros.

Applications of the first form, which backport `[[nodiscard]]` from a newer
dialect may be disabled using macros specific to the dialect it was added. For
example `_LIBCPP_DISABLE_NODISCARD_AFTER_CXX17`.

Applications of the second form, which are pure extensions, may be disabled
by defining `_LIBCPP_DISABLE_NODISCARD_EXT`.

This patch was originally written by me (Roman Lebedev),
then but then reworked by Eric Fiselier.

Reviewers: mclow.lists, thakis, EricWF

Reviewed By: thakis, EricWF

Subscribers: llvm-commits, mclow.lists, lebedev.ri, EricWF, rjmccall, Quuxplusone, cfe-commits, christof

Differential Revision: https://reviews.llvm.org/D45179

llvm-svn: 342808
2018-09-22 17:54:48 +00:00
Volodymyr Sapsai 8d6ac8f689 Revert "Implement LWG 2221 - No formatted output operator for nullptr."
This reverts r342566 as it causes on bots linker errors like

> Undefined symbols for architecture i386:
>   "std::__1::basic_ostream<char, std::__1::char_traits<char> >::operator<<(std::nullptr_t)", referenced from:

llvm-svn: 342599
2018-09-19 23:31:34 +00:00
Marshall Clow 4a71f9cfcc Implement LWG 2221 - No formatted output operator for nullptr. Reviewed as https://reviews.llvm.org/D44263
llvm-svn: 342566
2018-09-19 18:29:57 +00:00
Eric Fiselier 7dca3127c2 Don't require relops on variant alternatives to all return the same
type.

Libc++ correctly asserts that a set of visitors for a variant all
return the same type. However, we use the visitation machinary to
perform relational operations. This causes a static assertion when
some of the alternatives relops return a UDT which is implicitly
convertible to bool instead of 'bool' exactly.

llvm-svn: 342560
2018-09-19 17:53:21 +00:00
Fangrui Song cac6d21731 Fix typo
llvm-svn: 342361
2018-09-17 07:40:42 +00:00