Commit Graph

2989 Commits

Author SHA1 Message Date
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