Author: Louis Dionne Date: 2021-07-15T16:52:02-04:00 New Revision: a59165b01778a3b02c510a96951d115d39babd86
URL: https://github.com/llvm/llvm-project/commit/a59165b01778a3b02c510a96951d115d39babd86 DIFF: https://github.com/llvm/llvm-project/commit/a59165b01778a3b02c510a96951d115d39babd86.diff LOG: [runtimes] Don't try passing --target flags to GCC When a target triple is specified in CMake via XXX_TARGET_TRIPLE, we tried passing the --target=<...> flag to the compiler. However, not all compilers support that flag (e.g. GCC, which is not a cross-compiler). As a result, setting e.g. LIBCXX_TARGET_TRIPLE=<host-triple> would end up trying to pass --target=<host-triple> to GCC, which breaks everything because the flag isn't even supported. This commit only adds `--target=<...>` & friends to the flags if it is supported by the compiler. One could argue that it's confusing to pass LIBCXX_TARGET_TRIPLE=<...> and have it be ignored. That's correct, and one possibility would be to assert that the requested triple is the same as the host triple when we know the compiler is unable to cross-compile. However, note that this is a pre-existing issue (setting the TARGET_TRIPLE variable never had an influence on the flags passed to the compiler), and also fixing that is starting to look like reimplementing a lot of CMake logic that is already handled with CMAKE_CXX_COMPILER_TARGET. Differential Revision: https://reviews.llvm.org/D106082 Added: Modified: libcxx/CMakeLists.txt libcxx/cmake/Modules/HandleLibcxxFlags.cmake libcxxabi/CMakeLists.txt libcxxabi/cmake/Modules/HandleLibcxxabiFlags.cmake libunwind/CMakeLists.txt libunwind/cmake/Modules/HandleLibunwindFlags.cmake Removed: ################################################################################ diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt index 10caf0f8e3025..3025b6c4f37b5 100644 --- a/libcxx/CMakeLists.txt +++ b/libcxx/CMakeLists.txt @@ -465,17 +465,17 @@ include(HandleLibcxxFlags) add_target_flags_if(LIBCXX_BUILD_32_BITS "-m32") if(LIBCXX_TARGET_TRIPLE) - add_target_flags("--target=${LIBCXX_TARGET_TRIPLE}") + add_target_flags_if_supported("--target=${LIBCXX_TARGET_TRIPLE}") elseif(CMAKE_CXX_COMPILER_TARGET) set(LIBCXX_TARGET_TRIPLE "${CMAKE_CXX_COMPILER_TARGET}") endif() if(LIBCXX_SYSROOT) - add_target_flags("--sysroot=${LIBCXX_SYSROOT}") + add_target_flags_if_supported("--sysroot=${LIBCXX_SYSROOT}") elseif(CMAKE_SYSROOT) set(LIBCXX_SYSROOT "${CMAKE_SYSROOT}") endif() if(LIBCXX_GCC_TOOLCHAIN) - add_target_flags("--gcc-toolchain=${LIBCXX_GCC_TOOLCHAIN}") + add_target_flags_if_supported("--gcc-toolchain=${LIBCXX_GCC_TOOLCHAIN}") elseif(CMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN) set(LIBCXX_GCC_TOOLCHAIN "${CMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN}") endif() diff --git a/libcxx/cmake/Modules/HandleLibcxxFlags.cmake b/libcxx/cmake/Modules/HandleLibcxxFlags.cmake index a5b4df6600ee3..859cfc4a51559 100644 --- a/libcxx/cmake/Modules/HandleLibcxxFlags.cmake +++ b/libcxx/cmake/Modules/HandleLibcxxFlags.cmake @@ -121,6 +121,17 @@ macro(add_target_flags_if condition) endif() endmacro() +# Add all the flags supported by the compiler to all of +# 'CMAKE_CXX_FLAGS', 'CMAKE_C_FLAGS', 'LIBCXX_COMPILE_FLAGS' +# and 'LIBCXX_LINK_FLAGS'. +macro(add_target_flags_if_supported) + foreach(flag ${ARGN}) + mangle_name("${flag}" flagname) + check_cxx_compiler_flag("${flag}" "LIBCXX_SUPPORTS_${flagname}_FLAG") + add_target_flags_if(LIBCXX_SUPPORTS_${flagname}_FLAG ${flag}) + endforeach() +endmacro() + # Add a specified list of flags to both 'LIBCXX_COMPILE_FLAGS' and # 'LIBCXX_LINK_FLAGS'. macro(add_flags) diff --git a/libcxxabi/CMakeLists.txt b/libcxxabi/CMakeLists.txt index 584bcbd2adde6..8c21fc39d1857 100644 --- a/libcxxabi/CMakeLists.txt +++ b/libcxxabi/CMakeLists.txt @@ -258,17 +258,17 @@ include(HandleLibcxxabiFlags) add_target_flags_if(LIBCXXABI_BUILD_32_BITS "-m32") if(LIBCXXABI_TARGET_TRIPLE) - add_target_flags("--target=${LIBCXXABI_TARGET_TRIPLE}") + add_target_flags_if_supported("--target=${LIBCXXABI_TARGET_TRIPLE}") elseif(CMAKE_CXX_COMPILER_TARGET) set(LIBCXXABI_TARGET_TRIPLE "${CMAKE_CXX_COMPILER_TARGET}") endif() if(LIBCXX_GCC_TOOLCHAIN) - add_target_flags("--gcc-toolchain=${LIBCXXABI_GCC_TOOLCHAIN}") + add_target_flags_if_supported("--gcc-toolchain=${LIBCXXABI_GCC_TOOLCHAIN}") elseif(CMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN) set(LIBCXXABI_GCC_TOOLCHAIN "${CMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN}") endif() if(LIBCXXABI_SYSROOT) - add_target_flags("--sysroot=${LIBCXXABI_SYSROOT}") + add_target_flags_if_supported("--sysroot=${LIBCXXABI_SYSROOT}") elseif(CMAKE_SYSROOT) set(LIBCXXABI_SYSROOT "${CMAKE_SYSROOT}") endif() diff --git a/libcxxabi/cmake/Modules/HandleLibcxxabiFlags.cmake b/libcxxabi/cmake/Modules/HandleLibcxxabiFlags.cmake index 19d6e93b20b02..512e71a6a7805 100644 --- a/libcxxabi/cmake/Modules/HandleLibcxxabiFlags.cmake +++ b/libcxxabi/cmake/Modules/HandleLibcxxabiFlags.cmake @@ -123,6 +123,17 @@ macro(add_target_flags_if condition) endif() endmacro() +# Add all the flags supported by the compiler to all of +# 'CMAKE_CXX_FLAGS', 'CMAKE_C_FLAGS', 'LIBCXXABI_COMPILE_FLAGS' +# and 'LIBCXXABI_LINK_FLAGS'. +macro(add_target_flags_if_supported) + foreach(flag ${ARGN}) + mangle_name("${flag}" flagname) + check_cxx_compiler_flag("${flag}" "LIBCXXABI_SUPPORTS_${flagname}_FLAG") + add_target_flags_if(LIBCXXABI_SUPPORTS_${flagname}_FLAG ${flag}) + endforeach() +endmacro() + # Add a specified list of flags to both 'LIBCXXABI_COMPILE_FLAGS' and # 'LIBCXXABI_LINK_FLAGS'. macro(add_flags) diff --git a/libunwind/CMakeLists.txt b/libunwind/CMakeLists.txt index 9eada6895e009..9563328896676 100644 --- a/libunwind/CMakeLists.txt +++ b/libunwind/CMakeLists.txt @@ -152,17 +152,17 @@ include(HandleLibunwindFlags) add_target_flags_if(LIBUNWIND_BUILD_32_BITS "-m32") if(LIBUNWIND_TARGET_TRIPLE) - add_target_flags("--target=${LIBUNWIND_TARGET_TRIPLE}") + add_target_flags_if_supported("--target=${LIBUNWIND_TARGET_TRIPLE}") elseif(CMAKE_CXX_COMPILER_TARGET) set(LIBUNWIND_TARGET_TRIPLE "${CMAKE_CXX_COMPILER_TARGET}") endif() if(LIBUNWIND_GCC_TOOLCHAIN) - add_target_flags("--gcc-toolchain=${LIBUNWIND_GCC_TOOLCHAIN}") + add_target_flags_if_supported("--gcc-toolchain=${LIBUNWIND_GCC_TOOLCHAIN}") elseif(CMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN) set(LIBUNWIND_GCC_TOOLCHAIN "${CMAKE_CXX_COMPILER_EXTERNAL_TOOLCHAIN}") endif() if(LIBUNWIND_SYSROOT) - add_target_flags("--sysroot=${LIBUNWIND_SYSROOT}") + add_target_flags_if_supported("--sysroot=${LIBUNWIND_SYSROOT}") elseif(CMAKE_SYSROOT) set(LIBUNWIND_SYSROOT "${CMAKE_SYSROOT}") endif() diff --git a/libunwind/cmake/Modules/HandleLibunwindFlags.cmake b/libunwind/cmake/Modules/HandleLibunwindFlags.cmake index 57ba0b8cf7cd9..675071f9433fe 100644 --- a/libunwind/cmake/Modules/HandleLibunwindFlags.cmake +++ b/libunwind/cmake/Modules/HandleLibunwindFlags.cmake @@ -124,6 +124,17 @@ macro(add_target_flags_if condition) endif() endmacro() +# Add all the flags supported by the compiler to all of +# 'CMAKE_CXX_FLAGS', 'CMAKE_C_FLAGS', 'LIBUNWIND_COMPILE_FLAGS' +# and 'LIBUNWIND_LINK_FLAGS'. +macro(add_target_flags_if_supported) + foreach(flag ${ARGN}) + mangle_name("${flag}" flagname) + check_cxx_compiler_flag("${flag}" "LIBUNWIND_SUPPORTS_${flagname}_FLAG") + add_target_flags_if(LIBUNWIND_SUPPORTS_${flagname}_FLAG ${flag}) + endforeach() +endmacro() + # Add a specified list of flags to both 'LIBUNWIND_COMPILE_FLAGS' and # 'LIBUNWIND_LINK_FLAGS'. macro(add_flags) _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
