Attempt to unbreak Windows configuration. Although libc++ doesn't yet support Windows we still have Windows builders to track our progress. Currently the clang-cl configuration seems broken because it doesn't support -std=c++11 and instead requires /std:c++11. This patch attempts to fix this. git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@343431 91177308-0d34-0410-b5e6-96231b3b80d8 
diff --git a/CMakeLists.txt b/CMakeLists.txt index c87e356..fb866e1 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt 
@@ -53,6 +53,7 @@    if (MSVC)  set(LIBCXX_TARGETING_MSVC ON) + message(STATUS "Configuring for MSVC")  else()  set(LIBCXX_TARGETING_MSVC OFF)  endif() @@ -504,8 +505,10 @@  set(LIBCXX_STANDARD_VER c++14 CACHE INTERNAL "internal option to change build dialect")  endif()  add_compile_flags_if_supported(-std=${LIBCXX_STANDARD_VER}) +add_compile_flags_if_supported("/std:${LIBCXX_STANDARD_VER}")  mangle_name("LIBCXX_SUPPORTS_STD_EQ_${LIBCXX_STANDARD_VER}_FLAG" SUPPORTS_DIALECT_NAME) -if(NOT ${SUPPORTS_DIALECT_NAME}) +mangle_name("LIBCXX_SUPPORTS_STD_COLON_${LIBCXX_STANDARD_VER}_FLAG" SUPPORTS_DIALECT_NAME_MSVC) +if(NOT ${SUPPORTS_DIALECT_NAME} AND NOT ${SUPPORTS_DIALECT_NAME_MSVC})  if(NOT "${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC" AND NOT "${CMAKE_CXX_SIMULATE_ID}" STREQUAL "MSVC")  message(FATAL_ERROR "C++11 or greater is required but the compiler does not support ${LIBCXX_STANDARD_VER}")  endif()