Summary:
Starting in Clang 8.0 and GCC 8.0, `alignof` and `__alignof` return different values in same cases. Specifically `alignof` and `_Alignof` return the minimum alignment for a type, where as `__alignof` returns the preferred alignment. libc++ currently uses `__alignof` but means to use `alignof`. See llvm.org/PR39713
This patch introduces the macro `_LIBCPP_ALIGNOF` so we can control which spelling gets used.
This patch does not introduce any ABI guard to provide the old behavior with newer compilers. However, if we decide that is needed, this patch makes it trivial to implement.
I think we should commit this change immediately, and decide what we want to do about the ABI afterwards.
Reviewers: ldionne, EricWF
Reviewed By: EricWF
Subscribers: christof, libcxx-commits
Differential Revision: https://reviews.llvm.org/D54814
llvm-svn: 347787
Summary:
std::dynarray had been proposed for C++14, but it was pulled out from C++14
and there are no plans to standardize it anymore.
Reviewers: mclow.lists, EricWF
Subscribers: mgorny, christof, jkorous, dexonsmith, arphaman, libcxx-commits
Differential Revision: https://reviews.llvm.org/D54801
llvm-svn: 347783
This attribute should appear only on the first declaration. This
patch cleans up <string> by removing the attribute on redeclarations.
llvm-svn: 347608
This patch adds an implementation of __resize_default_init as
described in P1072R2. Additionally, it uses it in filesystem to
demonstrate its intended utility.
Once P1072 lands, or if it changes it's interface, I will adjust
the internal libc++ implementation to match.
llvm-svn: 347589
We don't support mac OS 10.6 and older anymore, so this macro can never
be defined. This bit of code had been added in D28931 as a fix for
PR31448, but it doesn't seem necessary anymore.
llvm-svn: 347427
r347395 changed the ABI list on Linux, but two of those symbols are still
being exported from the shared object:
_ZSt18make_exception_ptrINSt3__112future_errorEESt13exception_ptrT_
_ZNSt3__1plIcNS_11char_traitsIcEENS_9allocatorIcEEEENS_12basic_stringIT_T0_T1_EERKS9_PKS6_
This commit makes sure those symbols are not exported, as they should be.
llvm-svn: 347399
Summary:
This commit marks a few functions as hidden and removes them from the ABI list
on Linux such that libc++ can be built with -fvisibility=hidden. The functions
marked as hidden by this patch were exported from the shared object only
because they were implicitly instantiated function templates. It is safe
to stop exporting those symbols from the shared object because nobody could
actually depend on them: implicit instantiations are not taken from shared
objects.
The symbols removed in this commit are basically the same that had been
removed in https://reviews.llvm.org/D53868, but that patch had to be reverted
because it broke the build (because the functions were not marked as hidden
like this patch does).
Reviewers: EricWF, mclow.lists
Subscribers: christof, jkorous, dexonsmith, libcxx-commits
Differential Revision: https://reviews.llvm.org/D54639
llvm-svn: 347395
Summary:
P1006 adds support for constexpr in the specialization of pointer_traits
for raw pointers. This is necessary in order to use pointer_traits in
the upcoming constexpr containers. We expect P1006 to be voted into the
working draft for C++20 at the San Diego meeting.
Reviewers: mclow.lists, EricWF
Subscribers: christof, dexonsmith, libcxx-commits
Differential Revision: https://reviews.llvm.org/D53867
llvm-svn: 346764
shared_mutex was introduced in C++17 but its implementation currently
doesn't use Clang's thread annotations like regular mutex. This change
adds those.
Differential Revision: https://reviews.llvm.org/D54290
llvm-svn: 346567
This reverts r345525. I'm reverting because that patch apparently caused
a regression on certain platforms (see https://reviews.llvm.org/D53994).
Since we don't fully understand the reasons for the regression, I'm
reverting until we can provide a fix we understand.
llvm-svn: 345893
Summary:
This silences the two -Wimplicit-fallthrough warnings clang finds in
ItaniumDemangle.h in libc++abi.
Clang does not have a GNU attribute spelling for this attribute, so this
is necessary.
I will commit the same change to the LLVM demangler soon.
Reviewers: EricWF, ldionne
Subscribers: christof, erik.pilkington, cfe-commits
Differential Revision: https://reviews.llvm.org/D53985
llvm-svn: 345870
This commit adds a merge member function to all the map and set containers,
which splices nodes from the source container. This completes support for
P0083r3.
Differential revision: https://reviews.llvm.org/D48896
llvm-svn: 345744
Summary:
This patch makes the versioning namespace libc++ uses customizable by the user using `-DLIBCXX_ABI_NAMESPACE=__foo`.
This allows users to build custom versions of libc++ which can be linked into binaries with other libc++ versions without causing symbol conflicts or ODR issues.
Reviewers: mclow.lists, ldionne
Reviewed By: ldionne
Subscribers: kristina, smeenai, mgorny, phosek, libcxx-commits
Differential Revision: https://reviews.llvm.org/D53879
llvm-svn: 345657
Summary:
This commit adopts the exclude_from_explicit_instantiation attribute discussed
at [1] and reviewed in [2] in libc++ to supplant the use of __always_inline__
for visibility purposes.
This change means that users wanting to link together translation units built
with different versions of libc++'s headers into the same final linked image
MUST define the _LIBCPP_HIDE_FROM_ABI_PER_TU macro to 1 when building those
TUs. Doing otherwise will lead to ODR violations and ABI issues.
[1]: http://lists.llvm.org/pipermail/cfe-dev/2018-August/059024.html
[2]: https://reviews.llvm.org/D51789
Reviewers: rsmith, EricWF
Subscribers: dexonsmith, libcxx-commits
Differential Revision: https://reviews.llvm.org/D52405
llvm-svn: 345516
The types/comparators passed to std::upper_bound and std::lower_bound
are not required to provided to provide an operator</comp(...) which
accepts the arguments in reverse order. Nor are the ranges required
to have a strict weak ordering.
However, in debug mode we attempted to check the result of a comparison
with the arguments reversed, which may not compiler.
This patch removes the use of the debug comparator for upper_bound
and lower_bound.
equal_range et al still use debug comparators when they call
__upper_bound and __lower_bound.
See llvm.org/PR39458
llvm-svn: 345434
Summary:
C++14 sized deallocation is disabled by default due to ABI concerns. However, when a user manually enables it then libc++ should take advantage of it since sized deallocation can provide a significant performance win depending on the underlying malloc implementation. (Note that libc++'s definitions of sized delete don't do anything special yet, but users are free to provide their own).
This patch updates __libcpp_deallocate to selectively call sized operator delete when it's available. `__libcpp_deallocate_unsized` should be used when the size of the allocation is unknown.
On Apple this patch makes no attempt to determine if the sized operator delete is unavailable, only that the language feature is enabled. This could cause a compile error when using `std::allocator`, but the same compile error would occur whenever the user calls `new`, so I don't think it's a problem.
Reviewers: ldionne, mclow.lists
Reviewed By: ldionne
Subscribers: rsmith, ckennelly, libcxx-commits, christof
Differential Revision: https://reviews.llvm.org/D53120
llvm-svn: 345281
Summary:
When building with -fvisibility=hidden, some symbols do not get exported from
libc++.dylib. This means that some entities are not explicitly given default
visibility in the source code, and that we rely on the fact -fvisibility=default
is the default. This commit explicitly gives default visibility to those
symbols to avoid being dependent on the command line flags used.
The commit also remove symbols from the dylib -- those symbols do not
actually need to be exported from the dylib and this should not be an
ABI break.
Finally, in the future, we may want to mark the whole std:: namespace as
having hidden visibility (to switch from opt-out to opt-in), in which
case the changes done in this commit will be required.
Reviewers: EricWF
Subscribers: mgorny, christof, dexonsmith, libcxx-commits
Differential Revision: https://reviews.llvm.org/D52662
llvm-svn: 345260
Summary:
C++14 sized deallocation is disabled by default due to ABI concerns. However, when a user manually enables it then libc++ should take advantage of it since sized deallocation can provide a significant performance win depending on the underlying malloc implementation. (Note that libc++'s definitions of sized delete don't do anything special yet, but users are free to provide their own).
This patch updates __libcpp_deallocate to selectively call sized operator delete when it's available. `__libcpp_deallocate_unsized` should be used when the size of the allocation is unknown.
On Apple this patch makes no attempt to determine if the sized operator delete is unavailable, only that the language feature is enabled. This could cause a compile error when using `std::allocator`, but the same compile error would occur whenever the user calls `new`, so I don't think it's a problem.
Reviewers: ldionne, mclow.lists
Reviewed By: ldionne
Subscribers: rsmith, ckennelly, libcxx-commits, christof
Differential Revision: https://reviews.llvm.org/D53120
llvm-svn: 345214
This reverts commits r333103 and r333108. _Float16 and __fp16 are C11
extensions and compilers other than Clang don't define these for C++.
Differential Revision: https://reviews.llvm.org/D53670
llvm-svn: 345199
That macro has been defined to _LIBCPP_HIDE_FROM_ABI_AFTER_V1 for many
weeks now, so we're actually replacing uses of it for uses of
_LIBCPP_HIDE_FROM_ABI_AFTER_V1 directly.
This should not change or break anything since the two macros are
100% equivalent, unless somebody is (incorrectly!) relying on
_LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY being defined.
llvm-svn: 344641
Revert r344535 "Wrap up the new chrono literals in an #ifdef..."
Revert r344546 "Mark a couple of test cases as 'C++17-only'..."
Some of the buildbot failures were masked by another error,
and this one was probably missed.
llvm-svn: 344580
There are two cases:
1. The library has all it needs to provide align_val_t and the
new/delete overloads needed to support aligned allocation.
2. The compiler has actually turned the language feature on.
There are times where libc++ needs to distinguish between the two.
This patch adds the additional macro
_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION which denotes when case (1)
does not hold. _LIBCPP_HAS_NO_ALIGNED_ALLOCATION is defined whenever
_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION is defined, or when the
compiler has not enabled the language feature.
Additionally this patch cleans up a number of other macros related
to detection of aligned allocation machinery.
llvm-svn: 344207
Summary:
Scoped capabilities need to be annotated as such, otherwise the thread
safety analysis won't work as intended.
Fixes PR39234.
Reviewers: ldionne
Reviewed By: ldionne
Subscribers: christof, libcxx-commits
Differential Revision: https://reviews.llvm.org/D53049
llvm-svn: 344096
Summary:
Add error messages to a couple of static_asserts in span to match the
style used in the rest of the file. Also fix an extra paren typo in a
assert error message.
Committed on behalf of Jason Lovett.
Reviewers: ldionne
Subscribers: libcxx-commits
Differential Revision: https://reviews.llvm.org/D52841
llvm-svn: 343725
When we're using clang-cl and Microsoft's runtime implementation,
we don't provide align_val_t or aligned new/delete ourselves.
This patch updates the _LIBCPP_HAS_NO_ALIGNED_ALLOCATION macro
to reflect this.
llvm-svn: 343441
Summary:
The ABI version used by libc++ is a configuration option just like any other
configuration option. It is a knob that can be used by vendors to customize
the libc++ that they ship. As such, we should not be hardcoding vendor-specific
configuration choices in libc++.
When building libc++ for Fuchsia, Fuchsia's build scripts should simply define
the libc++ ABI version to 2 -- this will result in the _LIBCPP_ABI_VERSION
macro being defined in the __config header that is generated when libc++ is
built and installed, which is the correct way to customize libc++'s behavior
for specific vendors.
Reviewers: phosek, EricWF
Subscribers: mgorny, christof, dexonsmith, cfe-commits, libcxx-commits
Differential Revision: https://reviews.llvm.org/D52397
llvm-svn: 343079
Summary:
These deprecation warnings are opt-in: they are only enabled when the
_LIBCXX_DEPRECATION_WARNINGS macro is defined, which is not the case
by default. Note that this is a first step in the right direction, but
I wasn't able to get an exhaustive list of all deprecated components
per standard, so there's certainly stuff that's missing. The list of
components this commit marks as deprecated is:
in C++11:
- auto_ptr, auto_ptr_ref
- binder1st, binder2nd, bind1st(), bind2nd()
- pointer_to_unary_function, pointer_to_binary_function, ptr_fun()
- mem_fun_t, mem_fun1_t, const_mem_fun_t, const_mem_fun1_t, mem_fun()
- mem_fun_ref_t, mem_fun1_ref_t, const_mem_fun_ref_t, const_mem_fun1_ref_t, mem_fun_ref()
in C++14:
- random_shuffle()
in C++17:
- unary_negate, binary_negate, not1(), not2()
<rdar://problem/18168350>
Reviewers: mclow.lists, EricWF
Subscribers: christof, dexonsmith, llvm-commits
Differential Revision: https://reviews.llvm.org/D48912
llvm-svn: 342843
Summary:
The `[[nodiscard]]` attribute is intended to help users find bugs where
function return values are ignored when they shouldn't be. After C++17 the
C++ standard has started to declared such library functions as `[[nodiscard]]`.
However, this application is limited and applies only to dialects after C++17.
Users who want help diagnosing misuses of STL functions may desire a more
liberal application of `[[nodiscard]]`.
For this reason libc++ provides an extension that does just that! The
extension must be enabled by defining `_LIBCPP_ENABLE_NODISCARD`. The extended
applications of `[[nodiscard]]` takes two forms:
1. Backporting `[[nodiscard]]` to entities declared as such by the
standard in newer dialects, but not in the present one.
2. Extended applications of `[[nodiscard]]`, at the libraries discretion,
applied to entities never declared as such by the standard.
Users may also opt-out of additional applications `[[nodiscard]]` using
additional macros.
Applications of the first form, which backport `[[nodiscard]]` from a newer
dialect may be disabled using macros specific to the dialect it was added. For
example `_LIBCPP_DISABLE_NODISCARD_AFTER_CXX17`.
Applications of the second form, which are pure extensions, may be disabled
by defining `_LIBCPP_DISABLE_NODISCARD_EXT`.
This patch was originally written by me (Roman Lebedev),
then but then reworked by Eric Fiselier.
Reviewers: mclow.lists, thakis, EricWF
Reviewed By: thakis, EricWF
Subscribers: llvm-commits, mclow.lists, lebedev.ri, EricWF, rjmccall, Quuxplusone, cfe-commits, christof
Differential Revision: https://reviews.llvm.org/D45179
llvm-svn: 342808
This reverts r342566 as it causes on bots linker errors like
> Undefined symbols for architecture i386:
> "std::__1::basic_ostream<char, std::__1::char_traits<char> >::operator<<(std::nullptr_t)", referenced from:
llvm-svn: 342599
type.
Libc++ correctly asserts that a set of visitors for a variant all
return the same type. However, we use the visitation machinary to
perform relational operations. This causes a static assertion when
some of the alternatives relops return a UDT which is implicitly
convertible to bool instead of 'bool' exactly.
llvm-svn: 342560
Summary:
This commit fixes a regression introduced in r316095, where we don't match
inverted character classes when there's no negated characrers in the []'s.
rdar://problem/43060054
Reviewers: mclow.lists, timshen, EricWF
Subscribers: christof, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D50534
llvm-svn: 340609
Summary:
The state associated to the future was set in one thread (with synchronization)
but read in another thread without synchronization, which led to a data race.
https://bugs.llvm.org/show_bug.cgi?id=38181
rdar://problem/42548261
Reviewers: mclow.lists, EricWF
Subscribers: christof, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D51170
llvm-svn: 340608
These algorithms require a ForwardIterator or better. Ensure
we diagnose the contract violation at compile time instead of
of silently doing the wrong thing.
Further algorithms will be audited in upcoming patches.
llvm-svn: 340426
Summary:
The NetBSD headers ship with max_align_t, that is not
compatible with the fallback version in libc++.
There is no defined a compiler specific symbol in the headers like:
- __CLANG_MAX_ALIGN_T_DEFINED
- _GCC_MAX_ALIGN_T
- __DEFINED_max_align_t
Sponsored by <The NetBSD Foundation>
Reviewers: chandlerc, dlj, EricWF, joerg
Reviewed By: joerg
Subscribers: bsdjhb, llvm-commits, cfe-commits
Differential Revision: https://reviews.llvm.org/D47814
llvm-svn: 340224
Summary:
When a seed sequence would lead to having no non-zero significant bits
in the initial state of a `mersenne_twister_engine`, the fallback is to
flip the most significant bit of the first value that appears in the
textual representation of the initial state.
rand.eng.mers describes this as setting the value to be 2 to the power
of one less than w; the previous value encoded in the implementation,
namely one less than "2 to the power of w", is replaced by the correct
value in this patch.
Reviewers: mclow.lists, EricWF, jasonliu
Reviewed By: mclow.lists
Subscribers: mclow.lists, jasonliu, EricWF, christof, ldionne, cfe-commits
Differential Revision: https://reviews.llvm.org/D50736
llvm-svn: 339969
Summary:
https://reviews.llvm.org/D49240 led to symbol size problems in Chromium, and
we expect this may be the case in other projects built in debug mode too.
Instead, unless users explicitly ask for internal_linkage, we use always_inline
like we used to.
In the future, when we have a solution that allows us to drop always_inline
without falling back on internal_linkage, we can replace always_inline by
that.
Note that this commit introduces a change in contract for existing libc++
users: by default, libc++ used to guarantee that TUs built with different
versions of libc++ could be linked together. With the introduction of the
_LIBCPP_HIDE_FROM_ABI_PER_TU macro, the default behavior is that TUs built
with different libc++ versions are not guaranteed to link. This is a change
in contract but not a change in behavior, since the current implementation
still allows linking TUs built with different libc++ versions together.
Reviewers: EricWF, mclow.lists, dexonsmith, hans, rnk
Subscribers: christof, cfe-commits
Differential Revision: https://reviews.llvm.org/D50652
llvm-svn: 339874
This constructor needs to cast a pointer to uninitialized
memory to a pointer to object type in order to call
allocator_traits::construct(). This cast is not allowed when CFI cast
checks are enabled.
I did this instead of marking __addr() as _LIBCPP_NO_CFI so that we
don't lose CFI checks on get() or the dtor.
Differential Revision: https://reviews.llvm.org/D50743
llvm-svn: 339797
Summary:
The macros were inside `#if defined(_LIBCPP_COMPILER_CLANG)`, which means
we would never detect C11 features on non-Clang compilers. According to
Marshall Clow, this is not the intended behavior.
Reviewers: mclow.lists, EricWF
Subscribers: krytarowski, christof, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D50748
llvm-svn: 339741
Summary:
The current code enables aligned allocation functions when compiling in C++17
and later. This is a problem because aligned allocation functions might not
be supported on the target platform, which leads to an error at link time.
Since r338934, Clang knows not to define __cpp_aligned_new when it's not
available on the target platform -- this commit takes advantage of that to
only use aligned allocation functions when they are available.
Reviewers: vsapsai, EricWF
Subscribers: christof, dexonsmith, cfe-commits, EricWF, mclow.lists
Differential Revision: https://reviews.llvm.org/D50344
llvm-svn: 339431
Summary:
This macro allows hiding symbols from the ABI when the library is built
with an ABI version after ABI v1, which is currently the only stable ABI.
This commit defines `_LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY` to be
`_LIBCPP_HIDE_FROM_ABI_AFTER_V1`, meaning that symbols that were only
exported by the library for historical reasons are not exported anymore
in the unstable ABI.
Because of that, this commit is an ABI break for ABI v2. This ABI version
is not stable, however, so this should not be a problem.
Reviewers: EricWF, mclow.lists
Subscribers: christof, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D49914
llvm-svn: 339012
The warning happens when LIBCXX_ENABLE_EXCEPTIONS cmake option is not set,
and it fires every time __config is included, 33 in total.
Patch by Jason Lovett
Reviewed as https://reviews.llvm.org/D49997
llvm-svn: 338531
Marshall Clow