[CMake][libcxx] Use builtins rather than gcc_s when compiler-rt is requested
When compiler-rt is requested, we should attempt to link compiler-rt
builtins library rather than gcc_s.
Differential Revision: https://reviews.llvm.org/D31617
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@299599 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index e6f3b4c..bc15be6 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -83,7 +83,12 @@
add_library_flags_if(LIBCXX_HAS_C_LIB c)
add_library_flags_if(LIBCXX_HAS_M_LIB m)
add_library_flags_if(LIBCXX_HAS_RT_LIB rt)
-add_library_flags_if(LIBCXX_HAS_GCC_S_LIB gcc_s)
+if (LIBCXX_USE_COMPILER_RT)
+ find_compiler_rt_library(builtins LIBCXX_BUILTINS_LIBRARY)
+ add_library_flags_if(LIBCXX_BUILTINS_LIBRARY "${LIBCXX_BUILTINS_LIBRARY}")
+else()
+ add_library_flags_if(LIBCXX_HAS_GCC_S_LIB gcc_s)
+endif()
add_library_flags_if(LIBCXX_HAVE_CXX_ATOMICS_WITH_LIB atomic)
# Add the unwinder library.