This was caused by r281673, specifically changing `_LIBCPP_EXTERN_TEMPLATE_TYPE_VIS`
from `__attribute__((__type_visibility__("default")))` to
`__attribute__((__visibility("default")))`.
I made that change because I thought the external instantiations needed
their members to have default visibility. However since libc++ never builds
with -fvisibility=hidden this appears not to be needed. Instead this change
caused previously hidden inline methods to become un-hidden, which is a regression.
This patch reverts the problematic change and fixes PR30642.
llvm-svn: 283620
* Fix self-swap. Patch from Casey Carter.
* Remove workarounds and tests for types with deleted move constructors. This
was originally added as part of a LWG proposed resolution that has since
changed.
* Re-apply most recent PR for LWG 2769.
* Re-apply most recent PR for LWG 2754. Specifically fix the SFINAE checks to
use the decayed type.
* Fix tests to allow moved-from std::any's to have a non-empty state. This is
the behavior of MSVC's std::any.
* Various whitespace and test fixes.
llvm-svn: 283606
Summary:
The current implementation of `hash_code()` for uniqued RTTI strings violates strict aliasing by dereferencing a type-punned pointer. Specifically it generates a `const char**` pointer from the address of the `__name` member before casting it to `const size_t*` and dereferencing it to get the hash. This is really just a complex and incorrect way of writing `reinterpret_cast<size_t>(__name)`.
This patch changes the conversion sequence so that it no longer contains UB.
Reviewers: howard.hinnant, mclow.lists
Subscribers: rjmccall, cfe-commits
Differential Revision: https://reviews.llvm.org/D24012
llvm-svn: 283408
The libc-provided isnan/isinf/isfinite macro implementations are specifically
designed to function correctly, even in the presence of -ffast-math (or, more
specifically, -ffinite-math-only). As such, on most implementation, these
either always turn into external function calls (e.g. glibc) or are
specifically function calls when FINITE_MATH_ONLY is defined (e.g. Darwin).
Our implementation of complex arithmetic makes heavy use of isnan/isinf/isfinite
to deal with corner cases involving non-finite quantities. This was problematic
in two respects:
1. On systems where these are always function calls (e.g. Linux/glibc), there was a
performance penalty
2. When compiling with -ffast-math, there was a significant performance
penalty (in fact, on Darwin and systems with similar implementations, the code
may in fact be slower than not using -ffast-math, because the inline
definitions provided by libc become unavailable to prevent the checks from
being optimized out).
Eliding these inf/nan checks in -ffast-math mode is consistent with what
happens with libstdc++, and in my experience, what users expect. This is
critical to getting high-performance code when using complex<T>. This change
replaces uses of those functions on basic floating-point types with calls to
__builtin_isnan/isinf/isfinite, which Clang will always expand inline. When
using -ffast-math (or -ffinite-math-only), the optimizer will remove the checks
as expected.
Differential Revision: https://reviews.llvm.org/D18639
llvm-svn: 283051
Add underscore aliases for strtof_l and strtod_l. _strtold_l exists in
VS 2013 and above, so fix that definition as a drive-by fix.
Differential Revision: https://reviews.llvm.org/D25059
llvm-svn: 282681
Replace a stale reference to cxx_EXPORTS with _LIBCPP_BUILDING_LIBRARY,
and clarify why the operator new and delete family of functions are
marked dllexport when building but *not* dllimport when including the
header externally.
The new code is identical to the intent of the old code (and would be
functionally equivalent were cxx_EXPORTS still defined when building
libc++). The overall behavior is not ideal, since Microsoft's operator
new and delete functions will get called instead of libc++'s, but I
think consistently calling msvcrt's functions is better than either
calling msvcrt's or libc++'s functions depending on header inclusion.
Differential Revision: https://reviews.llvm.org/D25042
llvm-svn: 282644
builds.
On Windows the __declspec(dllimport) and __declspec(dllexport) attributes
require linking to a DLL, not a static library. Previously these annotations
were disabled by default unless _LIBCPP_DLL was defined. However the DLL
configuration is probably the more common one, so it should be supported by
default.
This patch enables import/export attributes by default and adds a
_LIBCPP_DISABLE_DLL_IMPORT_EXPORT macro which can be used to disable this
behavior. If libc++ is built as a static library on Windows then a custom __config
header will be generated that predefines this macro.
This patch is based off work by Shoaib Meenai.
llvm-svn: 282449
Summary: This patch fixes a couple of typos that cause compilation errors when application includes <unordered_map> and enables the libc++'s debugging capabilities.
Reviewers: EricWF
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D24883
llvm-svn: 282446
Summary:
`std::move` and `std::forward` were not marked constexpr in C++11. This can be very damaging because it makes otherwise constant expressions non-constant. For example:
```
#include <utility>
template <class T>
struct Foo {
constexpr Foo(T&& tx) : t(std::move(tx)) {}
T t;
};
[[clang::require_constant_initialization]] Foo<int> f(42); // Foo should be constant initialized but C++11 move is not constexpr. As a result `f` is an unsafe global.
```
This patch applies `constexpr` to `move` and `forward` as an extension in C++11. Normally the library is not allowed to add `constexpr` because it may be observable to the user. In particular adding constexpr may cause valid code to stop compiling. However these problems only happen in more complex situations, like making `__invoke(...)` constexpr. `forward` and `move` are simply enough that applying `constexpr` is safe.
Note that libstdc++ has offered this extension since at least 4.8.1.
Most of the changes in this patch are simply test cleanups or additions. The main changes in the tests are:
* Fold all `forward_N.fail.cpp` tests into a single `forward.fail.cpp` test using -verify.
* Delete most `move_only_N.fail.cpp` tests because they weren't actually testing anything.
* Fold `move_copy.pass.cpp` and `move_only.pass.cpp` into a single `move.pass.cpp` test.
* Add return type and noexcept tests for `forward` and `move`.
Reviewers: rsmith, mclow.lists, EricWF
Subscribers: K-ballo, loladiro
Differential Revision: https://reviews.llvm.org/D24637
llvm-svn: 282439
Declare __STDC_FORMAT_MACROS, __STDC_LIMIT_MACROS and
__STDC_CONSTANT_MACROS before including real inttypes.h/stdint.h when
the wrapper-header is included in C++11, in order to enable
the necessary macros in C99-compliant libc.
The C99 standard defined that the format macros in inttypes.h should be
defined by the C++ implementations only when __STDC_FORMAT_MACROS is
defined, and the limit and constant macros in stdint.h should be defined
only when __STDC_LIMIT_MACROS and __STDC_CONSTANT_MACROS are defined
appropriately. Following this specification, multiple old versions of
glibc up to 2.17 do not define those macros by default for C++,
rendering the libc++ headers non-compliant to the C++11 standard.
In order to achieve the necessary compliance, __STDC_FORMAT_MACROS is
defined in wrapped inttypes.h just before including the system
inttypes.h, when C++11 or newer is used. Both __STDC_LIMIT_MACROS
and __STDC_CONSTANT_MACROS are defined in newly-wrapped stdint.h. This
fixes the C++11 compliance while preserving the current behavior for
C++03.
Differential Revision: https://reviews.llvm.org/D24903
llvm-svn: 282435
Summary:
Libc++ still uses per-feature configuration macros when configuring for C++11. However libc++ requires a feature-complete C++11 compiler so there is no reason to check individual features. This patch starts the process of removing the feature specific macros and replacing their usage with `_LIBCPP_CXX03_LANG`.
This patch removes the __config macros:
* _LIBCPP_HAS_NO_TRAILING_RETURN
* _LIBCPP_HAS_NO_TEMPLATE_ALIASES
* _LIBCPP_HAS_NO_ADVANCED_SFINAE
* _LIBCPP_HAS_NO_DEFAULT_FUNCTION_TEMPLATE_ARGS
* _LIBCPP_HAS_NO_STATIC_ASSERT
As a drive I also changed our C++03 static_assert to use _Static_assert if available.
I plan to commit this without review if nobody voices an objection.
Reviewers: mclow.lists
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D24895
llvm-svn: 282347
Summary:
This patch has been a long time coming (Thanks @eugenis). It changes `_LIBCPP_INLINE_VISIBILITY` to use `__attribute__((internal_linkage))` instead of `__attribute__((visibility("hidden"), always_inline))`.
The point of `_LIBCPP_INLINE_VISIBILITY` is to prevent inline functions from being exported from both the libc++ library and from user libraries. This helps libc++ better manage it's ABI.
Previously this was done by forcing inlining and modifying the symbols visibility. However inlining isn't guaranteed and symbol visibility only affects shared libraries making this an imperfect solution. `internal_linkage` improves this situation by making all symbols local to the TU they are emitted in, regardless of inlining or visibility. IIRC the effect of applying `__attribute__((internal_linkage))` to an inline function is the same as applying `static`.
For more information about the attribute see: http://lists.llvm.org/pipermail/cfe-dev/2015-October/045580.html
Most of the work for this patch was done by @eugenis.
Reviewers: mclow.lists, eugenis
Subscribers: eugenis, cfe-commits
Differential Revision: https://reviews.llvm.org/D24642
llvm-svn: 282345
Visual Studio 2013 and onward have all the required functions in their
CRT headers, and we don't support older versions anymore.
Differential Revision: https://reviews.llvm.org/D24879
llvm-svn: 282328
On Windows, marking an `extern template class` declaration as exported
actually forces an instantiation, which is not the desired behavior.
Instead, the actual explicit instantiations need to be exported.
Differential Revision: https://reviews.llvm.org/D24679
llvm-svn: 281925
Summary:
None of these checks are specific to Android devices. If libc++ was
used with Bionic on a normal Linux system these checks would still be
needed.
Reviewers: mclow.lists, EricWF
Subscribers: compnerd, tberghammer, danalbert, srhines, cfe-commits
Differential Revision: https://reviews.llvm.org/D24690
llvm-svn: 281921
gcc and clang in gcc compatibility mode do not accept __forceinline. Use
the gcc attribute for them instead.
Differential Revision: https://reviews.llvm.org/D24678
llvm-svn: 281766
The externally instantiated member functions must be declared using
_LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY, not _LIBCPP_INLINE_VISIBILITY, in
order to be properly exported when using __attribute__((internal_linkage)).
Otherwise the explicit instantiations will obviously have internal linkage and
will not be exported from the dylib.
llvm-svn: 281684
Summary:
This patch fixes a number of problems with the visibility macros across GCC (on Unix) and Windows (DLL import/export semantics). All of the visibility macros are now documented under `DesignDocs/VisibilityMacros.rst`. Now I'll no longer forget the subtleties of each!
This patch adds two new visibility macros:
* `_LIBCPP_ENUM_VIS` for controlling the typeinfo of enum types. Only Clang supports this.
* `_LIBCPP_EXTERN_TEMPLATE_TYPE_VIS` for redefining visibility on explicit instantiation declarations. Clang and Windows require this.
After applying this patch GCC only emits one -Wattribute warning opposed to 30+.
Reviewers: mclow.lists, EricWF
Subscribers: beanz, mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D24602
llvm-svn: 281673
When `_LIBCPP_NO_EXCEPTIONS` is defined, we end up with compile errors
when targeting MSVCRT:
* Code includes `<new>`
* `<new>` includes `<cstdlib>` in order to get `abort`
* `<cstdlib>` includes `<stdlib.h>`, _before_ the `using ::abort`
* `<stdlib.h>` includes `locale_win32.h`
* `locale_win32.h` includes `<memory>`
* `<memory>` includes `<stdexcept>`
* `<stdexcept>` includes `<cstdlib` for `abort`, but that inclusion gets
(correctly) ignored because of header guards
* `<stdexcept>` references `_VSTD::abort`, which isn't declared
The easiest solution is to make `locale_win32.h` not include `<memory>`,
by removing the use of `unique_ptr` and manually restoring the locale
instead.
Differential Revision: https://reviews.llvm.org/D24374
llvm-svn: 281641
This patch causes a couple of issues:
1) It triggers http://llvm.org/PR30341. Although the bug is not truly a libc++
bug it breaks the LLVM build using libc++. Reverting this patch is only
a temporary workaround until Clang is fixed.
2) It adds yet another ABI incompatibility when libc++.so is compiled with GCC.
Specifically GCC doesn't ignore the _LIBCPP_INLINE_VISIBILITY on the out-of-line
definition when compiling the dylib. This causes the externally instantiated
~basic_string symbol to have hidden visibility.
This patch should be recommitted after addressing (1) and (2). (2) can be fixed
by adding _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY which is defined as
__attribute__((visibility("default"), always_inline)) as opposed to
_LIBCPP_INLINE_VISIBILITY which makes the symbol hidden.
llvm-svn: 281562
An enum class has associated type info. In the Microsoft ABI, type info
is emitted in the COMDAT section and isn't exported, so clang rightfully
complains about __declspec(dllexport) being unused for an enum class.
On other platforms, we still want to export the type info.
Differential Revision: https://reviews.llvm.org/D24065
llvm-svn: 281264
This patch further decouples libc++ from pthread, allowing libc++ to be built
against other threading systems. There are two main use cases:
- Building libc++ against a thread library other than pthreads.
- Building libc++ with an "external" thread API, allowing a separate library to
provide the implementation of that API.
The two use cases are quite similar, the second one being sligtly more
de-coupled than the first. The cmake option LIBCXX_HAS_EXTERNAL_THREAD_API
enables both kinds of builds. One needs to place an <__external_threading>
header file containing an implementation of the "libc++ thread API" declared
in the <__threading_support> header.
For the second use case, the implementation of the libc++ thread API can
delegate to a custom "external" thread API where the implementation of this
external API is provided in a seperate library. This mechanism allows toolchain
vendors to distribute a build of libc++ with a custom thread-porting-layer API
(which is the "external" API above), platform vendors (recipients of the
toolchain/libc++) are then required to provide their implementation of this API
to be linked with (end-user) C++ programs.
Note that the second use case still requires establishing the basic types that
get passed between the external thread library and the libc++ library
(e.g. __libcpp_mutex_t). These cannot be opaque pointer types (libc++ sources
won't compile otherwise). It should also be noted that the second use case can
have a slight performance penalty; as all the thread constructs need to cross a
library boundary through an additional function call.
When the header <__external_threading> is omitted, libc++ is built with the
"libc++ thread API" (declared in <__threading_support>) as the "external" thread
API (basic types are pthread based). An implementation (pthread based) of this
API is provided in test/support/external_threads.cpp, which is built into a
separate DSO and linked in when running the libc++ test suite. A test run
therefore demonstrates the second use case (less the intermediate custom API).
Differential revision: https://reviews.llvm.org/D21968
Reviewers: bcraig, compnerd, EricWF, mclow.lists
llvm-svn: 281179
Visual Studio 2013 (CRT version 12) added support for many C99 long long and
long double functions. Visual Studio 2015 (CRT version 14) increased C99 and C11
compliance further. Since we don't support Visual Studio versions older than
2013, we can considerably clean up the support header.
Patch by Shoaib Meenai!
llvm-svn: 280988
Author: laxmansole
Reviewers: howard.hinnant
mclow.lists
Subscribers: EricWF, flyingforyou, evandro
Differential Revision: https://reviews.llvm.org/D22834
Currently basic_string's destructor is not getting inlined. So adding 'inline' attribute to ~basic_string().
Worked in collaboration with Aditya Kumar.
llvm-svn: 280944
This patch fixes PR30260 by using a (void*) cast on the placement argument
to placement new to casts away the const. See also http://llvm.org/PR30260.
As a drive by change this patch also changes the header guard for
<experimental/optional> to _LIBCPP_EXPERIMENTAL_OPTIONAL from _LIBCPP_OPTIONAL.
llvm-svn: 280775
This patch removes the `<cstdlib>` include from exception where it is no longer
needed. Unlike my previous attempt this patch also adds <cstdlib> where needed
in other headers like <new> and <typeinfo>.
This won't fix the Firefox build issues discussed on IRC but it is more correct
for libc++.
llvm-svn: 280754
Apparently I missed a number of additional include which need to be added.
Reverting so I can recommit as a single patch with all of the required includes.
llvm-svn: 280752
call_once is using relaxed atomic load to perform double-checked locking, which contains a data race. The fast-path load has to be an acquire atomic load.
Differential Revision: https://reviews.llvm.org/D24028
llvm-svn: 280621
Summary:
This patch allows threads not created using `std::thread` to use `std::notify_all_at_thread_exit` by ensuring the TL state has been initialized within `std::notify_all_at_thread_exit`.
Additionally this patch "fixes" a potential oddity in `__thread_local_pointer::reset(pointer)`, which would previously delete the old thread local data. However there should *never* be old thread local data because pthread *should* null it out on thread exit. Unfortunately it's possible that pthread failed to do this according to the spec:
>
> Upon key creation, the value NULL shall be associated with the new key in all active threads. Upon thread creation, the value NULL shall be associated with all defined keys in the new thread.
>
> An optional destructor function may be associated with each key value. At thread exit, if a key value has a non-NULL destructor pointer, and the thread has a non-NULL value associated with that key, the value of the key is set to NULL, and then the function pointed to is called with the previously associated value as its sole argument. The order of destructor calls is unspecified if more than one destructor exists for a thread when it exits.
>
> If, after all the destructors have been called for all non-NULL values with associated destructors, there are still some non-NULL values with associated destructors, then the process is repeated. If, after at least {PTHREAD_DESTRUCTOR_ITERATIONS} iterations of destructor calls for outstanding non-NULL values, there are still some non-NULL values with associated destructors, implementations may stop calling destructors, or they may continue calling destructors until no non-NULL values with associated destructors exist, even though this might result in an infinite loop.
However if pthread fails to delete the value it is probably incorrect for us to do it. Destroying the value performs all of the "at thread exit" actions registered with it but we are way past "at thread exit".
Reviewers: mclow.lists, bcraig, EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D24159
llvm-svn: 280588
When <bitset> is compiled with warnings enabled, on a platform where
size_t is 4 bytes, it results in errors similar to:
bitset:265:16: error: non-constant-expression cannot be narrowed
from type 'unsigned long long' to '__storage_type' (aka 'unsigned
int') in initializer list [-Wc++11-narrowing]
: __first_{__v, __v >> __bits_per_word}
^~~
bitset:676:52: note: in instantiation of member function
'std::__1::__bitset<2, 53>::__bitset' requested here
bitset(unsigned long long __v) _NOEXCEPT : base(__v) {}
^
Fix these by casting the initializer list elements to __storage_type.
Reviewers: mclow.lists, EricWF
Differential Revision: https://reviews.llvm.org/D23960
llvm-svn: 280543
Microsoft removed gets from the CRT in Visual Studio 2015 onwards [1].
Attempting to reference it when targeting CRT versions 14 and above will cause
compile errors.
[1] https://msdn.microsoft.com/en-us/library/2029ea5f.aspx
Patch by Shoaib Meenai!
llvm-svn: 280417
Marshall Clow