Index: CMakeLists.txt =================================================================== --- CMakeLists.txt +++ CMakeLists.txt @@ -370,6 +370,10 @@ option(LLVM_ENABLE_PEDANTIC "Compile with pedantic enabled." ON) option(LLVM_ENABLE_WERROR "Fail and stop if a warning is triggered." OFF) +if (MSVC) + option(LLVM_ENABLE_INCREMENTAL_LINK "Link incrementally. Enabling it might produce slower executables." OFF) +endif() + option(LLVM_ENABLE_DUMP "Enable dump functions even when assertions are disabled" OFF) if( NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG" ) Index: cmake/modules/ChooseMSVCCRT.cmake =================================================================== --- cmake/modules/ChooseMSVCCRT.cmake +++ cmake/modules/ChooseMSVCCRT.cmake @@ -66,6 +66,15 @@ get_current_crt(LLVM_USE_CRT_${build} MSVC_CRT_REGEX CMAKE_CXX_FLAGS_${build}) + + # Make /MT the default in Release builds to make them faster + # and avoid the DLL function thunking. + if ((${build} STREQUAL "MINSIZEREL") OR + (${build} STREQUAL "RELEASE") OR + (${build} STREQUAL "RELWITHDEBINFO")) + set(LLVM_USE_CRT_${build} "MT") + endif() + set(LLVM_USE_CRT_${build} "${LLVM_USE_CRT_${build}}" CACHE STRING "Specify VC++ CRT to use for ${build_type} configurations." Index: cmake/modules/HandleLLVMOptions.cmake =================================================================== --- cmake/modules/HandleLLVMOptions.cmake +++ cmake/modules/HandleLLVMOptions.cmake @@ -381,6 +381,14 @@ # "Enforce type conversion rules". append("/Zc:rvalueCast" CMAKE_CXX_FLAGS) + if (CMAKE_CXX_COMPILER_ID MATCHES "MSVC" AND NOT LLVM_ENABLE_INCREMENTAL_LINK) + foreach(CONFIG RELEASE RELWITHDEBINFO MINSIZEREL) + foreach(FLAG EXE MODULE SHARED STATIC) + string(REGEX REPLACE "[-/](INCREMENTAL:YES|INCREMENTAL:NO|INCREMENTAL)" "/INCREMENTAL:NO" CMAKE_${FLAG}_LINKER_FLAGS_${CONFIG} "${CMAKE_${FLAG}_LINKER_FLAGS_${CONFIG}}") + endforeach() + endforeach() + endif() + if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND NOT LLVM_ENABLE_LTO) # clang-cl and cl by default produce non-deterministic binaries because # link.exe /incremental requires a timestamp in the .obj file. clang-cl