File libcxxabi-exceptions.patch of Package llvm

Index: libcxxabi-3.7.0.src/src/CMakeLists.txt
===================================================================
--- libcxxabi-3.7.0.src/src/CMakeLists.txt
+++ libcxxabi-3.7.0.src/src/CMakeLists.txt
@@ -52,7 +52,7 @@ append_if(libraries LIBCXXABI_HAS_PTHREA
 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_EH_LIB gcc_s)
 endif()
 
 # Setup flags.