1# Check if the host compiler is new enough. LLVM requires at least GCC 4.7, 2# MSVC 2013, or Clang 3.1. 3 4include(CheckCXXSourceCompiles) 5 6if(NOT DEFINED LLVM_COMPILER_CHECKED) 7 set(LLVM_COMPILER_CHECKED ON) 8 9 if(NOT LLVM_FORCE_USE_OLD_TOOLCHAIN) 10 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU") 11 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.7) 12 message(FATAL_ERROR "Host GCC version must be at least 4.7!") 13 endif() 14 elseif(CMAKE_CXX_COMPILER_ID STREQUAL "Clang") 15 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.1) 16 message(FATAL_ERROR "Host Clang version must be at least 3.1!") 17 endif() 18 19 if (CMAKE_CXX_SIMULATE_ID MATCHES "MSVC") 20 if (CMAKE_CXX_SIMULATE_VERSION VERSION_LESS 18.0) 21 message(FATAL_ERROR "Host Clang must have at least -fms-compatibility-version=18.0") 22 endif() 23 set(CLANG_CL 1) 24 elseif(NOT LLVM_ENABLE_LIBCXX) 25 # Otherwise, test that we aren't using too old of a version of libstdc++ 26 # with the Clang compiler. This is tricky as there is no real way to 27 # check the version of libstdc++ directly. Instead we test for a known 28 # bug in libstdc++4.6 that is fixed in libstdc++4.7. 29 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS}) 30 set(OLD_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES}) 31 set(CMAKE_REQUIRED_FLAGS "-std=c++0x") 32 check_cxx_source_compiles(" 33#include <atomic> 34std::atomic<float> x(0.0f); 35int main() { return (float)x; }" 36 LLVM_NO_OLD_LIBSTDCXX) 37 if(NOT LLVM_NO_OLD_LIBSTDCXX) 38 message(FATAL_ERROR "Host Clang must be able to find libstdc++4.7 or newer!") 39 endif() 40 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS}) 41 set(CMAKE_REQUIRED_LIBRARIES ${OLD_CMAKE_REQUIRED_LIBRARIES}) 42 endif() 43 elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC") 44 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 18.0) 45 message(FATAL_ERROR "Host Visual Studio must be at least 2013") 46 elseif(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 18.0.31101) 47 message(WARNING "Host Visual Studio should at least be 2013 Update 4 (MSVC 18.0.31101)" 48 " due to miscompiles from earlier versions") 49 endif() 50 endif() 51 endif() 52endif() 53