Commit Graph

597 Commits

Author SHA1 Message Date
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
Marshall Clow 2dda1ff038 Fix a '>= 0' test on unsigned that I inadvertantly introduced. Now correctly '!= 0'. Thanks to Arthur for the catch
llvm-svn: 363557
2019-06-17 13:41:14 +00:00
Marshall Clow 141c2b768d Recommit r362649, which was reverted in r262680 because of bugs in std::to_chars (which have now been fixed). Speedup to_string and to_wstring for integers using stack buffer and SSO
llvm-svn: 363003
2019-06-10 23:20:01 +00:00
Zhihao Yuan 6bc4a7685e [libc++] Fix leading zeros in std::to_chars
Summary:
It is a bugfix proposal for https://bugs.llvm.org/show_bug.cgi?id=42166.

`std::to_chars` appends leading zeros if input 64-bit value has 9, 10 or 11 digits.
According to documentation `std::to_chars` must not append leading zeros:
https://en.cppreference.com/w/cpp/utility/to_chars

Changeset should not affect `std::to_chars` performance:
http://quick-bench.com/CEpRs14xxA9WLvkXFtaJ3TWOVAg

Unit test that `std::from_chars` supports compatibility for both `std::to_chars` outputs (previous and fixed one) already exists:
1f60111b59/test/std/utilities/charconv/charconv.from.chars/integral.pass.cpp (L63)

Reviewers: lichray, mclow.lists, ldionne, EricWF

Reviewed By: lichray, mclow.lists

Subscribers: zoecarver, christof, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D63047

llvm-svn: 362967
2019-06-10 17:11:46 +00:00
Vlad Tsyrklevich bad2b3cf08 Revert "Speedup to_string and to_wstring for integers using stack buffer and SSO."
This reverts commit 7ce7110e6d, it was
causing sanitizer bot failures due to changing behavior of
std::to_string(). See https://reviews.llvm.org/D59178#1532023

llvm-svn: 362680
2019-06-06 07:51:39 +00:00
Marshall Clow 7ce7110e6d Speedup to_string and to_wstring for integers using stack buffer and SSO. Reviewed as https://reviews.llvm.org/D59178 Thanks to ivafanas for all his work on this patch.
llvm-svn: 362649
2019-06-05 21:04:26 +00:00
Marshall Clow 605d62e9de No longer reject inputs when using a locale that has grouping information _and_ the input has no grouping characters at all. We continue to reject cases when the input has grouping characters in the wrong place. Fixes PR#28704
llvm-svn: 362508
2019-06-04 15:18:46 +00:00
Petr Hosek 737de4d363 [libcxx] Use libtool when merging archives on Apple platforms
ar doesn't produce the correct results when used for linking static
archives on Apple platforms, so instead use libtool -static which is
the official way to build static archives on those platforms.

Differential Revision: https://reviews.llvm.org/D62770

llvm-svn: 362311
2019-06-02 01:14:31 +00:00
Petr Hosek b19977d5af [runtimes] Use _LIBCPP_HAS_COMMENT_LIB_PRAGMA in all relevant files
These two sources were omitted in r362055.

llvm-svn: 362061
2019-05-30 06:57:27 +00:00
Petr Hosek 789b7f0828 [runtimes] Check if pragma comment(lib, ...) is supported first
This fixes the issue introduced by r362048 where we always use
pragma comment(lib, ...) for dependent libraries when the compiler
is Clang, but older Clang versions don't support this pragma so
we need to check first if it's supported before using it.

llvm-svn: 362055
2019-05-30 04:40:21 +00:00
Petr Hosek 996e62eef7 [runtimes] Support ELF dependent libraries feature
As of r360984, LLD supports dependent libraries feature for ELF.
libunwind, libc++abi and libc++ have library dependencies: libdl librt
and libpthread, which means that when libunwind and libc++ are being
statically linked (using -static-libstdc++ flag), user has to manually
specify -ldl -lpthread which is onerous.

This change includes the lib pragma to specify the library dependencies
directly in the source that uses those libraries. This doesn't make any
difference when using linkers that don't support dependent libraries.
However, when using LLD that has dependent libraries feature, users no
longer have to manually specifying library dependencies when using
static linking, linker will pick the library automatically.

Differential Revision: https://reviews.llvm.org/D62090

llvm-svn: 362048
2019-05-30 01:34:41 +00:00
Petr Hosek 81f433b48c [runtimes] Move libunwind, libc++abi and libc++ to lib/$target/c++ and include/c++
This change is a consequence of the discussion in "RFC: Place libs in
Clang-dedicated directories", specifically the suggestion that
libunwind, libc++abi and libc++ shouldn't be using Clang resource
directory. Tools like clangd make this assumption, but this is
currently not true for the LLVM_ENABLE_PER_TARGET_RUNTIME_DIR build.
This change addresses that by moving the output of these libraries to
lib/$target/c++ and include/c++ directories, leaving resource directory
only for compiler-rt runtimes and Clang builtin headers.

Differential Revision: https://reviews.llvm.org/D59168

llvm-svn: 361432
2019-05-22 21:08:33 +00:00
Eric Fiselier f8d2d87fbb Speculative fix for std stream destruction order on Windows.
The MSVC CRT uses TLS storage to implement per-thread locales.
This storage gets freed during program termination, and if we attempt
to do any io operations (like flushing the std streams) after this occurs
the program may abort.

This patch is a speculative fix for that issue.

The fix tries forcing the initialization of the locale TLS before
initializing the std streams. This should mean that the TLS is freed
after we destroy the streams.

llvm-svn: 361348
2019-05-22 03:45:49 +00:00
Petr Hosek 741f52ca62 [libcxx] Don't use -fvisibility-global-new-delete-hidden when not defining them
When builing the hermetic static library, the compiler switch
-fvisibility-global-new-delete-hidden is necessary to get the new and
delete operator definitions made correctly. However, when those
definitions are not included in the library, then this switch does harm.
With lld (though not all linkers) setting STV_HIDDEN on SHN_UNDEF
symbols makes it an error to leave them undefined or defined via dynamic
linking that should generate PLTs for -shared linking (lld makes this a
hard error even without -z defs). Though leaving the symbols undefined
would usually work in practice if the linker were to allow it (and the
user didn't pass -z defs), this actually indicates a real problem that
could bite some target configurations more subtly at runtime. For
example, x86-32 ELF -fpic code generation uses hidden visibility on
declarations in the caller's scope as a signal that the call will never
be resolved to a PLT entry and so doesn't have to meet the special ABI
requirements for PLT calls (setting %ebx). Since these functions might
actually be resolved to PLT entries at link time (we don't know what the
user is linking in when the hermetic library doesn't provide all the
symbols itself), it's not safe for the compiler to treat their
declarations at call sites as having hidden visibility.

Differential Revision: https://reviews.llvm.org/D61571

llvm-svn: 360003
2019-05-06 01:22:28 +00:00
Louis Dionne 223ed705d0 [libc++][CMake] Link against libSystem on Apple platforms
Instead of manually linking against libm/librt/libpthread, we should be
linking against libSystem on Apple platforms, and only that. libm and
libpthread are symlinks to libSystem anyway.

llvm-svn: 359808
2019-05-02 17:43:48 +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
Petr Hosek f80c4b6348 [libcxx] Move CMake file to src, avoid using globs
This addresses the longstanding FIXME and makes libc++ build more
similar to other runtimes.

Differential Revision: https://reviews.llvm.org/D61275

llvm-svn: 359656
2019-05-01 06:40:36 +00:00
Chandler Carruth dd0a2e4461 Fix r359229 which tried to fix r359159...
When r359229 added noexcept to the declaration of `~mutex`, it didn't
add it to the definition which caused -Wimplicit-exception-spec-mismatch
to fire. This just adapts the definition to agree with the declaration.

llvm-svn: 359275
2019-04-26 05:04:33 +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
Louis Dionne d524fe5b3a [libc++] Remove redundant conditionals for Apple platforms
Summary:
In a bunch of places, we used to check whether LIBCXX_BUILDING_LIBCXXABI
is defined OR we're building for an Apple platform. This used to
be necessary in a time when Apple's build script did NOT define
LIBCXX_BUILDING_LIBCXXABI. However this is not relevant anymore
since Apple's build does define LIBCXX_BUILDING_LIBCXXABI.

Reviewers: EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D60842

llvm-svn: 358988
2019-04-23 14:05:04 +00:00
Louis Dionne a4bd340bf5 [libc++][CMake] Remove unnecessary conditional for defining new handlers
It turns out that whether the new handlers should be provided is orthogonal
to whether new/delete are provided in libc++ or libc++abi. The reason why
I initially added this conditional is because of an incorrect understanding
of the path we're taking when building on Apple platforms. In fact, we
always build libc++ on top of libc++abi on Apple platforms, so we take
the branch for `LIBCXX_BUILDING_LIBCXXABI` there.

llvm-svn: 358616
2019-04-17 21:57:49 +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
Louis Dionne cb843f5b55 [libc++][NFC] Make size of allocation more self-documenting
llvm-svn: 358588
2019-04-17 16:11:41 +00:00
Louis Dionne 3084db3bb1 [libc++] Remove old workaround for buildit
Summary:
I'm not sure what the problem was at the time, however I don't think
this is necessary since buildit doesn't exist anymore.

Instead of the workaround, the correct thing to do is to leave out
the get_new_handler/set_new_handler definitions from libc++ when
we're getting them from libc++abi.

Reviewers: EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D60717

llvm-svn: 358518
2019-04-16 19:26:56 +00:00
Marshall Clow 68ad5c34e0 Fix typo that I introduced in r357413. Thanks to ensadc@mailnesia.com for the catch.
llvm-svn: 357474
2019-04-02 14:00:36 +00:00
Marshall Clow ecad92b068 Fix PR#41323 'Race condition in steady_clock::now for _LIBCPP_WIN32API'. thanks to Ivan Afanasyev for the report.
llvm-svn: 357413
2019-04-01 17:23:30 +00:00
Thomas Anderson d4d824a861 [libc++] Fix return value of snprintf_l() on Windows when buffer is too small
When the output buffer is too small to contain the output, `vsnprintf()`
fills the buffer and returns the number of characters that __would have__
been written if the buffer was sufficiently large.

`_vnsprintf_s()` on the other hand fills the buffer and returns -1 when this
happens.  We want the former behavior, but we also want to be able to
pass in a locale to prevent having to call `setlocale()`.

`__stdio_common_vsprintf()` is the only function general enough to get
the behavior we want.

Differential Revision: https://reviews.llvm.org/D59727

llvm-svn: 357024
2019-03-26 19:51:30 +00:00
Louis Dionne f0d7d87a47 [NFC][libc++] Reindent #ifdefs
I don't understand why we don't always do that. We do it for normal `if`s
in the code, but not for preprocessor `if`s? It's a lot more readable when
indented properly.

llvm-svn: 356693
2019-03-21 18:19:21 +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
Thomas Anderson a0feccdf56 [libc++] Speed up certain locale functions on Windows
The issue is that __libcpp_locale_guard makes some slow calls to setlocale().
This change avoids using __libcpp_locale_guard in snprintf_l().

Fixes https://bugs.llvm.org/show_bug.cgi?id=41131

Differential Revision: https://reviews.llvm.org/D59525

llvm-svn: 356512
2019-03-19 20:30:58 +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
Eric Fiselier 7ffcd984c4 LWG 2843 "Unclear behavior of std::pmr::memory_resource::do_allocate()"
Patch by Arthur O'Dwyer.
Reviewed as https://reviews.llvm.org/D47344

new_delete_resource().allocate(n, a) has basically two permissible results:

* Return an appropriately sized and aligned block.
* Throw bad_alloc.

Before this patch, libc++'s new_delete_resource would do a third and impermissible thing, which was
to return an appropriately sized but inappropriately under-aligned block. This is now fixed.

(This came up while I was stress-testing unsynchronized_pool_resource on my MacBook. If we can't
trust the default resource to return appropriately aligned blocks, pretty much everything breaks.
For similar reasons, I would strongly support just patching __libcpp_allocate directly, but I don't
care to die on that hill, so I made this patch as a <memory_resource>-specific workaround.)

llvm-svn: 355763
2019-03-09 00:38:19 +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
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 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 1bccafe4f6 Handle cases where the dirent::d_type macros aren't defined
llvm-svn: 352942
2019-02-01 23:52:17 +00:00
Thomas Anderson 3663f26fb3 [libc++] Explicitly initialize std::nothrow
When building on Windows without libc++abi, this change fixes a build error of the form:

    src/new.cpp(38,17):  error: chosen constructor is explicit in copy-initialization
    const nothrow_t nothrow = {};
    include/vcruntime_new.h(53,22):  note: explicit constructor declared here
                explicit nothrow_t() = default;

Differential Revision: https://reviews.llvm.org/D57351

llvm-svn: 352648
2019-01-30 19:09:41 +00:00
Thomas Anderson 095ed0554f [libc++] Don't define exception destructors when using vcruntime
Exception destructors are provided by vcruntime.  Fixes link errors like:

    lld-link: error: duplicate symbol: "public: virtual __cdecl std::invalid_argument::~invalid_argument(void)" (??1invalid_argument@std@@UEAA@XZ) in stdexcept.obj and in libcpmt.lib(xthrow.obj)
    lld-link: error: duplicate symbol: "public: virtual __cdecl std::length_error::~length_error(void)" (??1length_error@std@@UEAA@XZ) in stdexcept.obj and in libcpmt.lib(xthrow.obj)
    lld-link: error: duplicate symbol: "public: virtual __cdecl std::out_of_range::~out_of_range(void)" (??1out_of_range@std@@UEAA@XZ) in stdexcept.obj and in libcpmt.lib(xthrow.obj)
    lld-link: error: duplicate symbol: "public: virtual __cdecl std::overflow_error::~overflow_error(void)" (??1overflow_error@std@@UEAA@XZ) in stdexcept.obj and in libcpmt.lib(xthrow.obj)

Differential Revision: https://reviews.llvm.org/D57425

llvm-svn: 352646
2019-01-30 19:07:30 +00:00
Marshall Clow 8681a3bc85 Commit D11348: 'Win32 support: wcsnrtombs and mbsnrtowcs don't handle null output buffers correctly' which has been hanging around for a long time
llvm-svn: 351971
2019-01-23 18:27:22 +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
Eric Fiselier 0e997efd53 [hurd] Fix unconditional use of PATH_MAX
Patch by Samuel Thibault

The GNU/Hurd system does not define an arbitrary PATH_MAX limitation, the POSIX 2001 realpath
extension can be used instead, and the size of symlinks can be determined.

Reviewed as https://reviews.llvm.org/D54677

llvm-svn: 351414
2019-01-17 02:59:28 +00:00
Dan Albert 45b511fb05 Fix size_t/off_t mixup in std::filesystem.
Summary: ftruncate takes an off_t, not a size_t.

Reviewers: EricWF, mclow.lists

Reviewed By: EricWF

Subscribers: christof, ldionne, libcxx-commits

Differential Revision: https://reviews.llvm.org/D56578

llvm-svn: 351226
2019-01-15 19:16:25 +00:00
Eric Fiselier ba62831f7c Implement LWG 3096: path::lexically_relative is confused by trailing slashes
path("/dir/").lexically_relative("/dir"); now returns "." instead of ""

llvm-svn: 349885
2018-12-21 04:25:40 +00:00
Eric Fiselier 1425485773 Implement LWG 2936: Path comparison is defined in terms of the generic format
This patch implements path::compare according to the current spec. The
only observable change is the ordering of "/foo" and "foo", which orders
the two paths based on having or not having a root directory (instead
of lexically comparing "/" to "foo").

llvm-svn: 349881
2018-12-21 03:16:30 +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 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 c9c6212f6f [libcxx] GNU/Hurd uses BSD-based interfaces, but does not (and won't) provide <sys/sysctl.h>
Reviewed as https://reviews.llvm.org/D54338.

Thanks to sthibaul for the patch.

llvm-svn: 346763
2018-11-13 17:00:04 +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 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