Don't clobber CMAKE_REQUIRED_FLAGS, it ends up being used in

C compilations as well and these flags don't make any sense there.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199756 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/cmake/modules/HandleLLVMOptions.cmake b/cmake/modules/HandleLLVMOptions.cmake
index cb7da4265806a4d28818582b1f26c0fd61e666fe..6c99682f76698213b5477ee0c6289576d854d584 100644 (file)
--- a/cmake/modules/HandleLLVMOptions.cmake
+++ b/cmake/modules/HandleLLVMOptions.cmake
@@ -29,6 +29,8 @@ if(NOT LLVM_FORCE_USE_OLD_TOOLCHAIN)
     # version of libstdc++ directly. Instead we test for a known bug in
     # libstdc++4.6 that is fixed in libstdc++4.7.
     if(NOT LLVM_ENABLE_LIBCXX)
+      set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
+      set(OLD_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
       set(CMAKE_REQUIRED_FLAGS "-std=c++0x")
       if (ANDROID)
         set(CMAKE_REQUIRED_LIBRARIES "atomic")
@@ -41,6 +43,8 @@ int main() { return (float)x; }"
       if(NOT LLVM_NO_OLD_LIBSTDCXX)
         message(FATAL_ERROR "Host Clang must be able to find libstdc++4.7 or newer!")
       endif()
+      set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
+      set(CMAKE_REQUIRED_LIBRARIES ${OLD_CMAKE_REQUIRED_LIBRARIES})
     endif()
   elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
     if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 17.0)