[libc++abi] Use libgcc and libgcc_s to provide _Unwind symbols instead of libgcc_eh.a

EricWF · EricWF · commit 3c9babc55ffe · 2015-12-14T22:20:04.000Z
Summary: libgcc_eh.a cannot be used when building libc++abi as a shared library (the default configuration). See this post for some more discussion: https://gcc.gnu.org/ml/gcc/2012-03/msg00104.html This patch reverts back to using libgcc_s when linking libc++abi.so. Reviewers: danalbert, chandlerc, mclow.lists, ismail, compnerd Subscribers: vkalintiris, cfe-commits Differential Revision: http://reviews.llvm.org/D15440 llvm-svn: 255559
diff --git a/libcxxabi/cmake/config-ix.cmake b/libcxxabi/cmake/config-ix.cmake
@@ -42,6 +42,6 @@ check_cxx_compiler_flag(/GR-                  LIBCXXABI_HAS_NO_GR_FLAG)
 check_library_exists(c fopen "" LIBCXXABI_HAS_C_LIB)
 check_library_exists(dl dladdr "" LIBCXXABI_HAS_DL_LIB)
 check_library_exists(pthread pthread_once "" LIBCXXABI_HAS_PTHREAD_LIB)
-check_library_exists(gcc_eh _Unwind_GetRegionStart "" LIBCXXABI_HAS_GCC_EH_LIB)
+check_library_exists(gcc_s __gcc_personality_v0 "" LIBCXXABI_HAS_GCC_S_LIB)
 check_library_exists(c __cxa_thread_atexit_impl ""
   LIBCXXABI_HAS_CXA_THREAD_ATEXIT_IMPL)
diff --git a/libcxxabi/src/CMakeLists.txt b/libcxxabi/src/CMakeLists.txt
@@ -40,17 +40,19 @@ if (LIBCXXABI_HAS_CXA_THREAD_ATEXIT_IMPL)
   add_definitions(-DHAVE___CXA_THREAD_ATEXIT_IMPL)
 endif()
 
-# Generate library list.
+# Generate library list
 set(libraries ${LIBCXXABI_CXX_ABI_LIBRARIES})
-append_if(libraries LIBCXXABI_HAS_C_LIB c)
+
 if (LIBCXXABI_ENABLE_THREADS)
   append_if(libraries LIBCXXABI_HAS_PTHREAD_LIB pthread)
 endif()
 
+append_if(libraries LIBCXXABI_HAS_C_LIB c)
+
 if (LIBCXXABI_USE_LLVM_UNWINDER)
   list(APPEND libraries unwind)
 else()
-  append_if(libraries LIBCXXABI_HAS_GCC_EH_LIB gcc_eh)
+  append_if(libraries LIBCXXABI_HAS_GCC_S_LIB gcc_s)
 endif()
 
 # Setup flags.
