1 # Check if the host compiler is new enough.
2 # These versions are updated based on the following policy:
3 # llvm.org/docs/DeveloperPolicy.html#toolchain
5 include(CheckCXXSourceCompiles)
8 set(GCC_SOFT_ERROR 7.4)
10 set(CLANG_SOFT_ERROR 5.0)
11 set(APPLECLANG_MIN 10.0)
12 set(APPLECLANG_SOFT_ERROR 10.0)
14 # https://en.wikipedia.org/wiki/Microsoft_Visual_C#Internal_version_numbering
15 # _MSC_VER == 1927 MSVC++ 14.27 Visual Studio 2019 Version 16.7
17 set(MSVC_SOFT_ERROR 19.27)
20 set(LIBSTDCXX_SOFT_ERROR 7)
23 if(DEFINED LLVM_COMPILER_CHECKED)
26 set(LLVM_COMPILER_CHECKED ON)
28 if(LLVM_FORCE_USE_OLD_TOOLCHAIN)
32 function(check_compiler_version NAME NICE_NAME MINIMUM_VERSION SOFT_ERROR_VERSION)
33 if(NOT CMAKE_CXX_COMPILER_ID STREQUAL NAME)
36 if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS MINIMUM_VERSION)
37 message(FATAL_ERROR "Host ${NICE_NAME} version must be at least ${MINIMUM_VERSION}, your version is ${CMAKE_CXX_COMPILER_VERSION}.")
38 elseif(CMAKE_CXX_COMPILER_VERSION VERSION_LESS SOFT_ERROR_VERSION)
39 if(LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN)
40 message(WARNING "Host ${NICE_NAME} version should be at least ${SOFT_ERROR_VERSION} because LLVM will soon use new C++ features which your toolchain version doesn't support. Your version is ${CMAKE_CXX_COMPILER_VERSION}. Ignoring because you've set LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.")
42 message(FATAL_ERROR "Host ${NICE_NAME} version should be at least ${SOFT_ERROR_VERSION} because LLVM will soon use new C++ features which your toolchain version doesn't support. Your version is ${CMAKE_CXX_COMPILER_VERSION}. You can temporarily opt out using LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.")
45 endfunction(check_compiler_version)
47 check_compiler_version("GNU" "GCC" ${GCC_MIN} ${GCC_SOFT_ERROR})
48 check_compiler_version("Clang" "Clang" ${CLANG_MIN} ${CLANG_SOFT_ERROR})
49 check_compiler_version("AppleClang" "Apple Clang" ${APPLECLANG_MIN} ${APPLECLANG_SOFT_ERROR})
50 check_compiler_version("MSVC" "Visual Studio" ${MSVC_MIN} ${MSVC_SOFT_ERROR})
52 # See https://developercommunity.visualstudio.com/content/problem/845933/miscompile-boolean-condition-deduced-to-be-always.html
53 # and thread "[llvm-dev] Longstanding failing tests - clang-tidy, MachO, Polly"
54 # on llvm-dev Jan 21-23 2020.
55 if ((${CMAKE_CXX_COMPILER_ID} STREQUAL MSVC) AND
56 (19.24 VERSION_LESS_EQUAL ${CMAKE_CXX_COMPILER_VERSION}) AND
57 (${CMAKE_CXX_COMPILER_VERSION} VERSION_LESS 19.25))
58 if(LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN)
59 message(WARNING "Host Visual Studio version 16.4 is known to miscompile part of LLVM")
61 message(FATAL_ERROR "Host Visual Studio version 16.4 is known to miscompile part of LLVM, please use clang-cl or upgrade to 16.5 or above (use -DLLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN=ON to ignore)")
66 if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
67 if (CMAKE_CXX_SIMULATE_ID MATCHES "MSVC")
68 if (CMAKE_CXX_SIMULATE_VERSION VERSION_LESS MSVC_MIN)
69 message(FATAL_ERROR "Host Clang must have at least -fms-compatibility-version=${MSVC_MIN}, your version is ${CMAKE_CXX_SIMULATE_VERSION}.")
72 elseif(NOT LLVM_ENABLE_LIBCXX)
73 # Test that we aren't using too old of a version of libstdc++.
74 set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
75 set(OLD_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
76 set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++0x")
77 check_cxx_source_compiles("
79 #if defined(__GLIBCXX__)
80 #if !defined(_GLIBCXX_RELEASE) || _GLIBCXX_RELEASE < ${LIBSTDCXX_MIN}
81 #error Unsupported libstdc++ version
84 int main() { return 0; }
87 if(NOT LLVM_LIBSTDCXX_MIN)
88 message(FATAL_ERROR "libstdc++ version must be at least ${GCC_MIN}.")
90 check_cxx_source_compiles("
92 #if defined(__GLIBCXX__)
93 #if !defined(_GLIBCXX_RELEASE) || _GLIBCXX_RELEASE < ${LIBSTDCXX_SOFT_ERROR}
94 #error Unsupported libstdc++ version
97 int main() { return 0; }
99 LLVM_LIBSTDCXX_SOFT_ERROR)
100 if(NOT LLVM_LIBSTDCXX_SOFT_ERROR)
101 if(LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN)
102 message(WARNING "libstdc++ version should be at least ${LIBSTDCXX_SOFT_ERROR} because LLVM will soon use new C++ features which your toolchain version doesn't support. Ignoring because you've set LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.")
104 message(FATAL_ERROR "libstdc++ version should be at least ${LIBSTDCXX_SOFT_ERROR} because LLVM will soon use new C++ features which your toolchain version doesn't support. You can temporarily opt out using LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.")
107 set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
108 set(CMAKE_REQUIRED_LIBRARIES ${OLD_CMAKE_REQUIRED_LIBRARIES})