cmake: Only add -pedantic if LLVM didn't add it. Don't unconditionally add

-Wall -W, since it's already provided by LLVM's cmake config, and that
overrides fixes (such as -Wno-uninitialized) which LLVM's cmake setup may have
provided.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180018 91177308-0d34-0410-b5e6-96231b3b80d8

CMakeLists.txt

@@ -137,7 +137,12 @@ configure_file(
 
 # Add appropriate flags for GCC
 if (LLVM_COMPILER_IS_GCC_COMPATIBLE)
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-common -Woverloaded-virtual -Wcast-qual -fno-strict-aliasing -pedantic -Wno-long-long -Wall -W -Wno-unused-parameter -Wwrite-strings")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-common -Woverloaded-virtual -Wcast-qual -fno-strict-aliasing")
+
+  # Enable -pedantic for Clang even if it's not enabled for LLVM.
+  if (NOT LLVM_ENABLE_PEDANTIC)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pedantic -Wno-long-long")
+  endif ()
 
   check_cxx_compiler_flag("-Werror -Wnested-anon-types" CXX_SUPPORTS_NO_NESTED_ANON_TYPES_FLAG)
   if( CXX_SUPPORTS_NO_NESTED_ANON_TYPES_FLAG )