From 45344cf7ac5b848f77825ffa37b0cb3b69b9b07b Mon Sep 17 00:00:00 2001 From: Raul Tambre Date: Thu, 20 Aug 2020 20:17:47 +0300 Subject: [PATCH] [CMake][compiler-rt][libunwind] Compile assembly files as ASM not C, unify workarounds It isn't very wise to pass an assembly file to the compiler and tell it to compile as a C file and hope that the compiler recognizes it as assembly instead. Simply don't mark the file as C and CMake will recognize the rest. This was attempted earlier in https://reviews.llvm.org/D85706, but reverted due to architecture issues on Apple. Subsequent digging revealed a similar change was done earlier for libunwind in https://reviews.llvm.org/rGb780df052dd2b246a760d00e00f7de9ebdab9d09. Afterwards workarounds were added for MinGW and Apple: * https://reviews.llvm.org/rGb780df052dd2b246a760d00e00f7de9ebdab9d09 * https://reviews.llvm.org/rGd4ded05ba851304b26a437896bc3962ef56f62cb The workarounds in libunwind and compiler-rt are unified and comments added pointing to each other. The workaround is updated to only be used for MinGW for CMake versions before 3.17, which fixed the issue (https://gitlab.kitware.com/cmake/cmake/-/merge_requests/4287). Additionally fixed Clang not being passed as the assembly compiler for compiler-rt runtime build. Example error: [525/634] Building C object lib/tsan/CMakeFiles/clang_rt.tsan-aarch64.dir/rtl/tsan_rtl_aarch64.S.o FAILED: lib/tsan/CMakeFiles/clang_rt.tsan-aarch64.dir/rtl/tsan_rtl_aarch64.S.o /opt/tooling/drive/host/bin/clang --target=aarch64-linux-gnu -I/opt/tooling/drive/llvm/compiler-rt/lib/tsan/.. -isystem /opt/tooling/drive/toolchain/opt/drive/toolchain/include -x c -Wall -Wno-unused-parameter -fno-lto -fPIC -fno-builtin -fno-exceptions -fomit-frame-pointer -funwind-tables -fno-stack-protector -fno-sanitize=safe-stack -fvisibility=hidden -fno-lto -O3 -gline-tables-only -Wno-gnu -Wno-variadic-macros -Wno-c99-extensions -Wno-non-virtual-dtor -fPIE -fno-rtti -Wframe-larger-than=530 -Wglobal-constructors --sysroot=. -MD -MT lib/tsan/CMakeFiles/clang_rt.tsan-aarch64.dir/rtl/tsan_rtl_aarch64.S.o -MF lib/tsan/CMakeFiles/clang_rt.tsan-aarch64.dir/rtl/tsan_rtl_aarch64.S.o.d -o lib/tsan/CMakeFiles/clang_rt.tsan-aarch64.dir/rtl/tsan_rtl_aarch64.S.o -c /opt/tooling/drive/llvm/compiler-rt/lib/tsan/rtl/tsan_rtl_aarch64.S /opt/tooling/drive/llvm/compiler-rt/lib/tsan/rtl/tsan_rtl_aarch64.S:29:1: error: expected identifier or '(' .section .text ^ 1 error generated. Differential Revision: https://reviews.llvm.org/D86308 --- clang/runtime/CMakeLists.txt | 1 + compiler-rt/cmake/Modules/AddCompilerRT.cmake | 10 +++++----- libunwind/src/CMakeLists.txt | 12 ++++-------- 3 files changed, 10 insertions(+), 13 deletions(-) diff --git a/clang/runtime/CMakeLists.txt b/clang/runtime/CMakeLists.txt index e20cc26..61bbbf8 100644 --- a/clang/runtime/CMakeLists.txt +++ b/clang/runtime/CMakeLists.txt @@ -75,6 +75,7 @@ if(LLVM_BUILD_EXTERNAL_COMPILER_RT AND EXISTS ${COMPILER_RT_SRC_ROOT}/) CMAKE_ARGS ${CLANG_COMPILER_RT_CMAKE_ARGS} -DCMAKE_C_COMPILER=${LLVM_RUNTIME_OUTPUT_INTDIR}/clang -DCMAKE_CXX_COMPILER=${LLVM_RUNTIME_OUTPUT_INTDIR}/clang++ + -DCMAKE_ASM_COMPILER=${LLVM_RUNTIME_OUTPUT_INTDIR}/clang -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DCMAKE_MAKE_PROGRAM=${CMAKE_MAKE_PROGRAM} -DLLVM_CONFIG_PATH=${LLVM_RUNTIME_OUTPUT_INTDIR}/llvm-config diff --git a/compiler-rt/cmake/Modules/AddCompilerRT.cmake b/compiler-rt/cmake/Modules/AddCompilerRT.cmake index efb6608..f2f0b5e 100644 --- a/compiler-rt/cmake/Modules/AddCompilerRT.cmake +++ b/compiler-rt/cmake/Modules/AddCompilerRT.cmake @@ -109,11 +109,11 @@ endfunction() function(add_asm_sources output) set(${output} ${ARGN} PARENT_SCOPE) - # Xcode will try to compile asm files as C ('clang -x c'), and that will fail. - if (${CMAKE_GENERATOR} STREQUAL "Xcode") - enable_language(ASM) - else() - # Pass ASM file directly to the C++ compiler. + # CMake doesn't pass the correct architecture for Apple prior to CMake 3.19. https://gitlab.kitware.com/cmake/cmake/-/issues/20771 + # MinGW didn't work correctly with assembly prior to CMake 3.17. https://gitlab.kitware.com/cmake/cmake/-/merge_requests/4287 and https://reviews.llvm.org/rGb780df052dd2b246a760d00e00f7de9ebdab9d09 + # Workaround these two issues by compiling as C. + # Same workaround used in libunwind. Also update there if changed here. + if((APPLE AND CMAKE_VERSION VERSION_LESS 3.19) OR (MINGW AND CMAKE_VERSION VERSION_LESS 3.17)) set_source_files_properties(${ARGN} PROPERTIES LANGUAGE C) endif() endfunction() diff --git a/libunwind/src/CMakeLists.txt b/libunwind/src/CMakeLists.txt index 928bc59..0944917 100644 --- a/libunwind/src/CMakeLists.txt +++ b/libunwind/src/CMakeLists.txt @@ -24,14 +24,10 @@ set(LIBUNWIND_ASM_SOURCES UnwindRegistersRestore.S UnwindRegistersSave.S ) -if (MINGW OR APPLE) - # CMake doesn't build assembly sources for windows/gnu targets properly - # (up to current CMake, 3.16), so treat them as C files. - # Additionally, CMake ignores OSX_ARCHITECTURE for ASM files when targeting - # Apple platforms. - set_source_files_properties(${LIBUNWIND_ASM_SOURCES} - PROPERTIES - LANGUAGE C) + +# See add_asm_sources() in compiler-rt for explanation of this workaround. +if((APPLE AND CMAKE_VERSION VERSION_LESS 3.19) OR (MINGW AND CMAKE_VERSION VERSION_LESS 3.17)) + set_source_files_properties(${LIBUNWIND_ASM_SOURCES} PROPERTIES LANGUAGE C) endif() set(LIBUNWIND_HEADERS -- 2.7.4