Summary:
Freestanding is *weird*. The standard allows it to differ in a bunch of odd
manners from regular C++, and the committee would like to improve that
situation. I'd like to make libc++ behave better with what freestanding should
be, so that it can be a tool we use in improving the standard. To do that we
need to try stuff out, both with "freestanding the language mode" and
"freestanding the library subset".
Let's start with the super basic: run the libc++ tests in freestanding, using
clang as the compiler, and see what works. The easiest hack to do this:
In utils/libcxx/test/config.py add:
self.cxx.compile_flags += ['-ffreestanding']
Run the tests and they all fail.
Why? Because in freestanding `main` isn't special. This "not special" property
has two effects: main doesn't get mangled, and main isn't allowed to omit its
`return` statement. The first means main gets mangled and the linker can't
create a valid executable for us to test. The second means we spew out warnings
(ew) and the compiler doesn't insert the `return` we omitted, and main just
falls of the end and does whatever undefined behavior (if you're luck, ud2
leading to non-zero return code).
Let's start my work with the basics. This patch changes all libc++ tests to
declare `main` as `int main(int, char**` so it mangles consistently (enabling us
to declare another `extern "C"` main for freestanding which calls the mangled
one), and adds `return 0;` to all places where it was missing. This touches 6124
files, and I apologize.
The former was done with The Magic Of Sed.
The later was done with a (not quite correct but decent) clang tool:
https://gist.github.com/jfbastien/793819ff360baa845483dde81170feed
This works for most tests, though I did have to adjust a few places when e.g.
the test runs with `-x c`, macros are used for main (such as for the filesystem
tests), etc.
Once this is in we can create a freestanding bot which will prevent further
regressions. After that, we can start the real work of supporting C++
freestanding fairly well in libc++.
<rdar://problem/47754795>
Reviewers: ldionne, mclow.lists, EricWF
Subscribers: christof, jkorous, dexonsmith, arphaman, miyuki, libcxx-commits
Differential Revision: https://reviews.llvm.org/D57624
llvm-svn: 353086
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
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
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
The standard section [array.zero] requires the return value of begin()
and end() methods of a zero-sized array to be unique. Eric Fiselier
clarifies: "That unique value cannot be null, and must be properly aligned".
This patch adds checks for the first part of this clarification: unique
value returned by these methods cannot be null.
Reviewed as https://reviews.llvm.org/D55366.
Thanks to Andrey Maksimov for the patch.
llvm-svn: 348509
The section array.zero says: "The return value of data() is unspecified".
This patch marks all checks of the array<T, 0>.data() return value as
libc++ specific.
Reviewed as https://reviews.llvm.org/D55364.
Thanks to Andrey Maksimov for the patch.
llvm-svn: 348485
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
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
The iterator types for different specializations of containers with the
same element type but different allocators are not required to be
convertible. This patch makes the test to take the iterator type from
the same container specialization as the created container.
Reviewed as https://reviews.llvm.org/D54806.
Thanks to Andrey Maksimov for the patch.
llvm-svn: 347423
Some tests use type std::max_align_t, but don't include <cstddef> header
directly. As a result, these tests won't compile against some conformant
libraries.
Reviewed as https://reviews.llvm.org/D54645.
Thanks to Andrey Maksimov for the patch.
llvm-svn: 347232
This was implicitly converting [1, 3] to bool, which triggers
an MSVC warning. The test should just pass `true`, which is
simpler, has the same behavior, and avoids the warning. (This
is a library test, not a compiler test, and the conversion happens
before calling `push_back`, so passing [1, 3] isn't interesting
in any way. This resembles a previous change to stop passing
`1 == 1` in the `vector<bool>` tests.)
llvm-svn: 346910
C++2a[container.requirements.general]p8 states that when move constructing
a container, the allocator is move constructed. Vector previously copy
constructed these allocators. This patch fixes that bug.
Additionally it cleans up some unnecessary allocator conversions
when copy constructing containers. Libc++ uses
__internal_allocator_traits::select_on_copy_construction to select
the correct allocator during copy construction, but it unnecessarily
converted the resulting allocator to the user specified allocator
type and back. After this patch list and forward_list no longer
do that.
Technically we're supposed to be using allocator_traits<allocator_type>::select_on_copy_construction,
but that should seemingly be addressed as a separate patch, if at all.
llvm-svn: 334053
An array T[1] isn't necessarily the same say when it's
a member of a struct. This patch addresses that problem and corrects
the tests to deal with it.
llvm-svn: 324545
Summary:
This patch fixes llvm.org/PR35491 and LWG2157 (https://cplusplus.github.io/LWG/issue2157)
The fix attempts to maintain ABI compatibility by replacing the array with a instance of `aligned_storage`.
Reviewers: mclow.lists, EricWF
Reviewed By: EricWF
Subscribers: lichray, cfe-commits
Differential Revision: https://reviews.llvm.org/D41223
llvm-svn: 324526
Revert "Fix initialization of array<const T, 0> with GCC."
Revert "Make array<const T, 0> non-CopyAssignable and make swap and fill ill-formed."
This reverts commit r324182, r324185, and r324194 which were causing issues with zero-length std::arrays.
llvm-svn: 324309
The standard isn't exactly clear how std::array should handle zero-sized arrays
with const element types. In particular W.R.T. copy assignment, swap, and fill.
This patch takes the position that those operations should be ill-formed,
and makes changes to libc++ to make it so.
This follows up on commit r324182.
llvm-svn: 324185
Summary:
This patch fixes llvm.org/PR35491 and LWG2157 (https://cplusplus.github.io/LWG/issue2157)
The fix attempts to maintain ABI compatibility by replacing the array with a instance of `aligned_storage`.
Reviewers: mclow.lists, EricWF
Reviewed By: EricWF
Subscribers: lichray, cfe-commits
Differential Revision: https://reviews.llvm.org/D41223
llvm-svn: 324182
In a17cd7c641c34b6c4bd4845a4d4fb590cb6c238c Marshall added assert(true) to the vector<bool>::size tests, which break on C1XX:
D:\Contest\gl0qojfu.5pe\src\qa\vc\libs\libcxx\upstream\test\std\containers\sequences\vector.bool\size.pass.cpp(62): error C2220: warning treated as error - no 'object' file generated
d:\contest\gl0qojfu.5pe\src\qa\vc\libs\libcxx\upstream\test\std\containers\sequences\vector.bool\size.pass.cpp(33) : warning C6326: Potential comparison of a constant with another constant.
d:\contest\gl0qojfu.5pe\src\qa\vc\libs\libcxx\upstream\test\std\containers\sequences\vector.bool\size.pass.cpp(52) : warning C6326: Potential comparison of a constant with another constant.
The corresponding test for vector::size asserts assert(c.size() == 3);, so I changed it to do that here.
llvm-svn: 318812
Summary:
The constructors `vector(Iter, Iter, Alloc = Alloc{})` and `assign(Iter, Iter)` don't correctly perform EmplaceConstruction from the result of dereferencing the iterator. This results in them performing an additional and unneeded copy.
This patch addresses the issue by correctly using `emplace_back` in C++11 and newer.
There are also some bugs in our `insert` implementation, but those will be handled separately.
@mclow.lists We should probably merge this into 5.1, agreed?
Reviewers: mclow.lists, dlj, EricWF
Reviewed By: mclow.lists, EricWF
Subscribers: cfe-commits, mclow.lists
Differential Revision: https://reviews.llvm.org/D38757
llvm-svn: 315994
This makes them consistent (many comments already used uppercase).
The special REQUIRES, UNSUPPORTED, and XFAIL comments are excluded from this change.
llvm-svn: 309468
This patch cleans up all usages of the following feature test macros inside
<vector> and its tests:
* _LIBCPP_HAS_NO_RVALUE_REFERENCES
* _LIBCPP_HAS_NO_VARIADICS
* _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
Where needed the above guards were replaced with _LIBCPP_CXX03_LANG.
llvm-svn: 300410
Summary:
By manipulating a local variable in the loop, when the loop can
be optimized away (due to no non-trivial destructors), this lets
it be fully optimized away and we modify the __end_ separately.
This results in a substantial improvement in the generated code.
Prior to this change, this would be generated (on x86_64):
movq (%rdi), %rdx
movq 8(%rdi), %rcx
cmpq %rdx, %rcx
je LBB2_2
leaq -12(%rcx), %rax
subq %rdx, %rax
movabsq $-6148914691236517205, %rdx ## imm = 0xAAAAAAAAAAAAAAAB
mulq %rdx
shrq $3, %rdx
notq %rdx
leaq (%rdx,%rdx,2), %rax
leaq (%rcx,%rax,4), %rax
movq %rax, 8(%rdi)
And after:
movq (%rdi), %rax
movq %rax, 8(%rdi)
This brings this in line with what other implementations do.
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D25241
llvm-svn: 298601
Guard typedefs and static_asserts with _LIBCPP_VERSION.
test/std/containers/sequences/vector.bool/move_assign_noexcept.pass.cpp
test/std/containers/sequences/vector.bool/move_noexcept.pass.cpp
test/std/containers/sequences/vector.bool/swap_noexcept.pass.cpp
Additionally deal with conditional compilation.
test/std/containers/associative/map/map.cons/move_noexcept.pass.cpp
test/std/containers/associative/multimap/multimap.cons/move_noexcept.pass.cpp
Additionally deal with typedefs used by other typedefs.
Fixes D29135.
llvm-svn: 294154
Summary:
Exactly what the title says.
This patch also adds a `std::hash<nullptr_t>` specialization in C++17, but it was not added by this paper and I can't find the actual paper that adds it.
See http://wg21.link/P0513R0 for more info.
If there are no comments in the next couple of days I'll commit this
Reviewers: mclow.lists, K-ballo, EricWF
Reviewed By: EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D28938
llvm-svn: 292684
MSVC has compiler warnings C4127 "conditional expression is constant" (enabled
by /W4) and C6326 "Potential comparison of a constant with another constant"
(enabled by /analyze). They're potentially useful, although they're slightly
annoying to library devs who know what they're doing. In the latest version of
the compiler, C4127 is suppressed when the compiler sees simple tests like
"if (name_of_thing)", so extracting comparison expressions into named
constants is a workaround. At the same time, using std::integral_constant
avoids C6326, which doesn't look at template arguments.
test/std/containers/sequences/vector.bool/emplace.pass.cpp
Replace 1 == 1 with true, which is the same as far as the library is concerned.
Fixes D28837.
llvm-svn: 292432
In list::remove we collect the nodes we're removing in a seperate
list instance. However we construct this list using the default
constructor which default constructs the allocator. However allocators
are not required to be default constructible. This patch fixes the
construction of the second list.
llvm-svn: 289735
test/std/containers/container.adaptors/queue/queue.cons.alloc/ctor_container_alloc.pass.cpp
test/std/containers/container.adaptors/stack/stack.cons.alloc/ctor_container_alloc.pass.cpp
Iterate with C::size_type because that's what operator[] takes.
test/std/containers/sequences/vector/contiguous.pass.cpp
test/std/strings/basic.string/string.require/contiguous.pass.cpp
Add static_cast<typename C::difference_type> because that's what the iterator's operator+ takes.
Fixes D27777.
llvm-svn: 289734
These swap tests were swapping non-POCS non-equal allocators which
is undefined behavior. This patch changes the tests to use allocators
which compare equal. In order to test that the allocators were not
swapped I added an "id" field to test_allocator which does not
participate in equality but does propagate across copies/swaps.
This patch is based off of D26623 which was submitted by STL.
llvm-svn: 289358
test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_rand.pass.cpp
(Affects 64-bit architectures.) Include <cstddef> so we can take/return std::ptrdiff_t
(instead of int) in random_shuffle()'s RNG. (C++14 D.12 [depr.alg.random.shuffle]/2 says that
difference_type is used, and we're shuffling a plain array.)
test/std/algorithms/alg.sorting/alg.sort/sort/sort.pass.cpp
test/std/algorithms/alg.sorting/alg.sort/stable.sort/stable_sort.pass.cpp
(Affects 64-bit architectures.) Include <iterator> because we're already using iterator_traits.
Then, store the result of subtracting two RanIts as difference_type instead of long
(which truncates on LLP64 architectures like MSVC x64).
test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_flist.pass.cpp
test/std/containers/sequences/forwardlist/forwardlist.ops/splice_after_one.pass.cpp
(Affects 64-bit architectures.) Include <cstddef> so we can store the result of
subtracting two pointers as std::ptrdiff_t (instead of int).
test/std/input.output/iostream.format/input.streams/istream.unformatted/ignore_0xff.pass.cpp
(Affects 32-bit architectures.) Sometimes, size_t is too small. That's the case here,
where tellg() returns pos_type (N4606 27.7.2.3 [istream.unformatted]/39). Implementations can
have 64-bit pos_type (to handle large files) even when they have 32-bit size_t.
Fixes D27543.
llvm-svn: 289110
test/std/containers/sequences/vector.bool/copy.pass.cpp
test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
test/std/containers/sequences/vector/vector.cons/copy.pass.cpp
test/std/containers/sequences/vector/vector.cons/copy_alloc.pass.cpp
Change "unsigned s = x.size();" to "typename C::size_type s = x.size();"
because that's what it returns.
test/std/strings/basic.string/string.cons/pointer_alloc.pass.cpp
Include <cstddef>, then change "unsigned n = T::length(s);"
to "std::size_t n = T::length(s);" because that's what char_traits returns.
test/std/strings/basic.string/string.cons/substr.pass.cpp
Change unsigned to typename S::size_type because that's what str.size() returns.
test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp
This was needlessly truncating std::size_t to unsigned.
It's being used to compare and initialize std::size_t.
llvm-svn: 288753
Various changes:
test/std/algorithms/alg.sorting/alg.merge/inplace_merge.pass.cpp
This is comparing value_type to unsigned. value_type is sometimes int and sometimes struct S (implicitly constructible from int).
static_cast<value_type>(unsigned) silences the warning and doesn't do anything bad (as the values in question are small).
test/std/algorithms/alg.sorting/alg.nth.element/nth_element_comp.pass.cpp
This is comparing an int remote-element to size_t. The values in question are small and non-negative,
so either type is fine. I think that converting int to size_t is marginally better here than the reverse.
test/std/containers/sequences/deque/deque.cons/size.pass.cpp
DefaultOnly::count is int (and non-negative). When comparing to unsigned, use static_cast<unsigned>.
test/std/strings/basic.string/string.access/index.pass.cpp
We're comparing char to '0' through '9', but formed with the type size_t. Add static_cast<char>.
test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp
Include <cstddef> for pedantic correctness (this test was already mentioning std::size_t).
"v[i] == (i & 1)" was comparing bool to size_t. Saying "v[i] == ((i & 1) != 0)" smashes the RHS to bool.
llvm-svn: 288749
Change "unsigned n = 0;" to "int n = 0;". It's being compared to int elements and ptrdiff_t distances.
test/std/containers/sequences/forwardlist/forwardlist.cons/move.pass.cpp
This one's a little special, but not really. "*i == n" is comparing MoveOnly to n.
MoveOnly is implicitly constructible from int, so int is the correct type to use here.
llvm-svn: 288748
Add static_cast<int>. In these cases, the values are guaranteed to be small-ish,
and they're being compared to int elements.
test/std/containers/sequences/deque/deque.capacity/access.pass.cpp
Use int instead of unsigned to iterate from 0 to 10.
llvm-svn: 288747
Marshall Clow