diff options
| -rw-r--r-- | CMakeLists.txt | 6 | ||||
| -rw-r--r-- | cmake/modules/LLVMProcessSources.cmake | 10 |
2 files changed, 16 insertions, 0 deletions
diff --git a/CMakeLists.txt b/CMakeLists.txt index 3f48b58f43..5e27c6f82e 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -317,6 +317,12 @@ if( MINGW ) set(CMAKE_C_STANDARD_LIBRARIES "${CMAKE_C_STANDARD_LIBRARIES}${LLVM_SYSTEM_LIBS}") endif() +if( MINGW ) + # People report that -O3 is unreliable on MinGW. The traditional + # build also uses -O2 for that reason: + llvm_replace_compiler_option(CMAKE_CXX_FLAGS_RELEASE "-O3" "-O2") +endif() + add_subdirectory(lib/Support) # Everything else depends on Support: diff --git a/cmake/modules/LLVMProcessSources.cmake b/cmake/modules/LLVMProcessSources.cmake index 5f59eac451..98b61296db 100644 --- a/cmake/modules/LLVMProcessSources.cmake +++ b/cmake/modules/LLVMProcessSources.cmake @@ -1,5 +1,15 @@ include(AddFileDependencies) +macro(llvm_replace_compiler_option var old new) + # Replaces a compiler option or switch `old' in `var' by `new'. + # If `old' is not in `var', appends `new' to `var'. + # Example: llvm_replace_compiler_option(CMAKE_CXX_FLAGS_RELEASE "-O3" "-O2") + if( "${${var}}" MATCHES "(^| )${old}($| )" ) + string( REGEX REPLACE "(^| )${old}($| )" " ${new} " ${var} "${${var}}" ) + else() + set( ${var} "${${var}} ${new}" ) + endif() +endmacro(llvm_replace_compiler_option) macro(add_td_sources srcs) file(GLOB tds *.td) |