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
When libc++experimental was originally created it was empty and therefore there
was no reason to install it. Now that the library contains
<experimental/memory_resource> and <experimental/filesystem> there is a good
reason to install it.
Specifically this patch enables the installation whenever LIBCXX_INSTALL_LIBRARY
is true and LIBCPP_ENABLE_EXPERIMENTAL_LIBRARY is true.
llvm-svn: 280773
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
`-fPIC` doesn't make much sense for Windows, since Windows DLLs aren't compiled
position independent and are instead relocated at runtime.
Patch by Shoaib Meenai!
llvm-svn: 280413
In r280108 I tried to make the headers copy relative to LLVM_BINARY_DIR, and the intent was that it would only happen on in-tree builds or runtimes directory builds. It didn't actually work that way.
This patch adds a check for CMAKE_SOURCE_DIR being equal to CMAKE_CURRENT_SOURCE_DIR. In this case we set a variable LIBCXX_USING_INSTLLED_LLVM. This doesn't necessarily mean the LLVM is installed (it could be a build directory), but it means we need to treat the LLVM directory as read-only.
llvm-svn: 280400
Summary: This copy phase is only needed for in-tree builds, so we should be copying to the LLVM build directory's include dir instead of the sub-project include dir.
Reviewers: bogner, EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D24015
llvm-svn: 280108
Some of the mutex tests fail on machines with high load. This patch implements
the test directive "// FLAKY_TEST" which allows a test to be run 3 times
before it's considered a failure.
llvm-svn: 280050
We're compiling libc++ with -nodefaultlibs, so we should also pass this
option during the configuration checks to ensure those checks are
consistent with the actual build.
The primary motivation here is to ease cross-compilation against a
non-standard set of C++ libraries. Previously, the configuration checks
would attempt to link against the standard C++ libraries, which would
cause link failures when cross-compiling, even though the actual library
link would go through correctly (because of the use of -nodefaultlibs
and explicitly specifying any needed libraries). This is more correct
even ignoring the motivation, however.
Patch by Shoaib Meenai!
llvm-svn: 280015
Summary:
Currently a number of GCC warnings are emitted when building libc++. This patch fixes or ignores all of them. The primary changes are:
* Work around strict aliasing issues in `typeinfo::hash_code()` by using __attribute__((may_alias)). However I think a non-aliasing `hash_code()` implementation is possible. Further investigation needed.
* Add `_LIBCPP_UNREACHABLE()` to switch in `strstream.cpp` to avoid -Wpotentially-uninitialized.
* Fix -Wunused-value warning in `__all` by adding a void cast.
* Ignore -Wattributes for now. There are a number of real attribute issues when using GCC but enabling the warning is too noisy.
* Ignore -Wliteral-suffix since it warns about the use of reserved identifiers. Note Only GCC 7.0 supports disabling this warning.
* Ignore -Wc++14-compat since it warns about the sized new/delete overloads.
Reviewers: EricWF
Differential Revision: https://reviews.llvm.org/D24003
llvm-svn: 280007
This patch enables the `cxx-benchmarks` target by default. Note that the target
still has to be manually invoked since it isn't included in the default 'make'
rule.
This patch also gets the benchmarks building w/ GCC. The build previously
required the '-stdlib=libc++' flag but upstream patches to Google Benchmark
now allow the library to build w/ libc++ and GCC.
These changes should make the benchmarks easier to build and test.
llvm-svn: 279999
This assignment operator was previously broken since the SFINAE always resulted
in substitution failure. This caused assignments to turn into
copy construction + assignment.
This patch was originally committed as r279953 but was reverted due to warnings
in the test-suite. This new patch corrects those warnings.
llvm-svn: 279955
This assignment operator was previously broken since the SFINAE always resulted
in substitution failure. This caused assignments to turn into
copy construction + assignment.
llvm-svn: 279953
This patch implements the std::sample function added to C++17 from LFTS. It
also removes the std::experimental::sample implementation which now forwards
to std::sample.
llvm-svn: 279948
Libc++'s implementation of shuffle and sample already support lvalue and rvalue
RNG's. This patch adds tests for both categories and marks the issue as complete.
This patch also contains drive-by change for std::experimental::sample which
improves the diagnostics produced when the correct iterator categories are
not supplied.
llvm-svn: 279947
Similar to rL242623, move C++ version checks outside of _NOEXCEPT_()
macro invocation argument lists, to avoid "embedding a directive within
macro arguments has undefined behavior" warnings.
Differential Revision: https://reviews.llvm.org/D23961
llvm-svn: 279926
