llvm-project/libcxx/include/__config_site.in

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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP_CONFIG_SITE
#define _LIBCPP_CONFIG_SITE
#cmakedefine _LIBCPP_ABI_VERSION @_LIBCPP_ABI_VERSION@
#cmakedefine _LIBCPP_ABI_UNSTABLE
#cmakedefine _LIBCPP_ABI_FORCE_ITANIUM
#cmakedefine _LIBCPP_ABI_FORCE_MICROSOFT
#cmakedefine _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE
#cmakedefine _LIBCPP_HAS_NO_STDIN
#cmakedefine _LIBCPP_HAS_NO_STDOUT
#cmakedefine _LIBCPP_HAS_NO_THREADS
#cmakedefine _LIBCPP_HAS_NO_MONOTONIC_CLOCK
#cmakedefine _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
#cmakedefine _LIBCPP_HAS_MUSL_LIBC
#cmakedefine _LIBCPP_HAS_THREAD_API_PTHREAD
[libcxx] Introduce an externally-threaded libc++ variant. 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
2016-09-12 05:46:40 +08:00
#cmakedefine _LIBCPP_HAS_THREAD_API_EXTERNAL
#cmakedefine _LIBCPP_HAS_THREAD_LIBRARY_EXTERNAL
#cmakedefine _LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS
#cmakedefine _LIBCPP_NO_VCRUNTIME
@_LIBCPP_ABI_DEFINES@
#endif // _LIBCPP_CONFIG_SITE