[libcxx-commits] [libcxxabi] r362055 - [runtimes] Check if pragma comment(lib, ...) is supported first

[Petr Hosek via libcxx-commits]

Author: phosek
Date: Wed May 29 21:40:21 2019
New Revision: 362055

URL: http://llvm.org/viewvc/llvm-project?rev=362055&view=rev
Log:
[runtimes] Check if pragma comment(lib, ...) is supported first

This fixes the issue introduced by r362048 where we always use
pragma comment(lib, ...) for dependent libraries when the compiler
is Clang, but older Clang versions don't support this pragma so
we need to check first if it's supported before using it.

Modified:
    libcxxabi/trunk/CMakeLists.txt
    libcxxabi/trunk/cmake/config-ix.cmake
    libcxxabi/trunk/src/cxa_exception_storage.cpp
    libcxxabi/trunk/src/cxa_guard_impl.h
    libcxxabi/trunk/src/cxa_thread_atexit.cpp
    libcxxabi/trunk/src/fallback_malloc.cpp

Modified: libcxxabi/trunk/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/CMakeLists.txt?rev=362055&r1=362054&r2=362055&view=diff
==============================================================================
--- libcxxabi/trunk/CMakeLists.txt (original)
+++ libcxxabi/trunk/CMakeLists.txt Wed May 29 21:40:21 2019
@@ -441,6 +441,10 @@ if (LIBCXXABI_BAREMETAL)
     add_definitions(-DLIBCXXABI_BAREMETAL)
 endif()
 
+if (LIBCXXABI_HAS_COMMENT_LIB_PRAGMA)
+  add_definitions(-D_LIBCXXABI_HAS_COMMENT_LIB_PRAGMA)
+endif()
+
 string(REPLACE ";" " " LIBCXXABI_CXX_FLAGS "${LIBCXXABI_CXX_FLAGS}")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${LIBCXXABI_CXX_FLAGS}")
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${LIBCXXABI_C_FLAGS}")

Modified: libcxxabi/trunk/cmake/config-ix.cmake
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/cmake/config-ix.cmake?rev=362055&r1=362054&r2=362055&view=diff
==============================================================================
--- libcxxabi/trunk/cmake/config-ix.cmake (original)
+++ libcxxabi/trunk/cmake/config-ix.cmake Wed May 29 21:40:21 2019
@@ -1,6 +1,7 @@
 include(CheckLibraryExists)
 include(CheckCCompilerFlag)
 include(CheckCXXCompilerFlag)
+include(CheckCSourceCompiles)
 
 check_library_exists(c fopen "" LIBCXXABI_HAS_C_LIB)
 if (NOT LIBCXXABI_USE_COMPILER_RT)
@@ -48,6 +49,14 @@ if (LIBCXXABI_HAS_NODEFAULTLIBS_FLAG)
   endif ()
 endif ()
 
+# Check compiler pragmas
+if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+  check_c_source_compiles("
+#pragma comment(lib, \"c\")
+int main() { return 0; }
+" LIBCXXABI_HAS_COMMENT_LIB_PRAGMA)
+endif()
+
 # Check compiler flags
 check_c_compiler_flag(-funwind-tables         LIBCXXABI_HAS_FUNWIND_TABLES)
 check_cxx_compiler_flag(-fno-exceptions       LIBCXXABI_HAS_NO_EXCEPTIONS_FLAG)

Modified: libcxxabi/trunk/src/cxa_exception_storage.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/cxa_exception_storage.cpp?rev=362055&r1=362054&r2=362055&view=diff
==============================================================================
--- libcxxabi/trunk/src/cxa_exception_storage.cpp (original)
+++ libcxxabi/trunk/src/cxa_exception_storage.cpp Wed May 29 21:40:21 2019
@@ -46,6 +46,10 @@ extern "C" {
 #include "abort_message.h"
 #include "fallback_malloc.h"
 
+#if defined(__unix__) &&  defined(__ELF__) && defined(_LIBCXXABI_HAS_COMMENT_LIB_PRAGMA)
+#pragma comment(lib, "pthread")
+#endif
+
 //  In general, we treat all threading errors as fatal.
 //  We cannot call std::terminate() because that will in turn
 //  call __cxa_get_globals() and cause infinite recursion.

Modified: libcxxabi/trunk/src/cxa_guard_impl.h
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/cxa_guard_impl.h?rev=362055&r1=362054&r2=362055&view=diff
==============================================================================
--- libcxxabi/trunk/src/cxa_guard_impl.h (original)
+++ libcxxabi/trunk/src/cxa_guard_impl.h Wed May 29 21:40:21 2019
@@ -50,7 +50,7 @@
 #include <stdlib.h>
 #include <__threading_support>
 #ifndef _LIBCXXABI_HAS_NO_THREADS
-#if defined(__unix__) &&  defined(__ELF__) && defined(__clang__)
+#if defined(__unix__) &&  defined(__ELF__) && defined(_LIBCXXABI_HAS_COMMENT_LIB_PRAGMA)
 #pragma comment(lib, "pthread")
 #endif
 #endif

Modified: libcxxabi/trunk/src/cxa_thread_atexit.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/cxa_thread_atexit.cpp?rev=362055&r1=362054&r2=362055&view=diff
==============================================================================
--- libcxxabi/trunk/src/cxa_thread_atexit.cpp (original)
+++ libcxxabi/trunk/src/cxa_thread_atexit.cpp Wed May 29 21:40:21 2019
@@ -10,7 +10,7 @@
 #include "cxxabi.h"
 #include <__threading_support>
 #ifndef _LIBCXXABI_HAS_NO_THREADS
-#if defined(__unix__) &&  defined(__ELF__) && defined(__clang__)
+#if defined(__unix__) &&  defined(__ELF__) && defined(_LIBCXXABI_HAS_COMMENT_LIB_PRAGMA)
 #pragma comment(lib, "pthread")
 #endif
 #endif

Modified: libcxxabi/trunk/src/fallback_malloc.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/fallback_malloc.cpp?rev=362055&r1=362054&r2=362055&view=diff
==============================================================================
--- libcxxabi/trunk/src/fallback_malloc.cpp (original)
+++ libcxxabi/trunk/src/fallback_malloc.cpp Wed May 29 21:40:21 2019
@@ -13,7 +13,7 @@
 
 #include <__threading_support>
 #ifndef _LIBCXXABI_HAS_NO_THREADS
-#if defined(__unix__) &&  defined(__ELF__) && defined(__clang__)
+#if defined(__unix__) &&  defined(__ELF__) && defined(_LIBCXXABI_HAS_COMMENT_LIB_PRAGMA)
 #pragma comment(lib, "pthread")
 #endif
 #endif