set(STAMP_DIR ${CMAKE_CURRENT_BINARY_DIR}/bootstrap-stamps/)
set(BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR}/bootstrap-bins/)
+ # If on Darwin we need to make bootstrap depend on LTO and pass
+ # DARWIN_LTO_LIBRARY so that -flto will work using the just-built compiler
+ if(APPLE)
+ set(LTO_DEP LTO llvm-ar llvm-ranlib)
+ set(LTO_LIBRARY -DDARWIN_LTO_LIBRARY=${CMAKE_BINARY_DIR}/lib/libLTO.dylib)
+ set(LTO_AR -DCMAKE_AR=${CMAKE_BINARY_DIR}/bin/llvm-ar)
+ set(LTO_RANLIB -DCMAKE_RANLIB=${CMAKE_BINARY_DIR}/bin/llvm-ranlib)
+ endif()
+
add_custom_target(bootstrap-clear
DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/bootstrap-cleared
)
add_custom_command(
OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/bootstrap-cleared
- DEPENDS clang
+ DEPENDS clang ${LTO_DEP}
COMMAND ${CMAKE_COMMAND} -E remove_directory ${BINARY_DIR}
COMMAND ${CMAKE_COMMAND} -E make_directory ${BINARY_DIR}
COMMAND ${CMAKE_COMMAND} -E remove_directory ${STAMP_DIR}
)
ExternalProject_Add(bootstrap
- DEPENDS clang
+ DEPENDS clang ${LTO_DEP}
PREFIX bootstrap
SOURCE_DIR ${CMAKE_SOURCE_DIR}
STAMP_DIR ${STAMP_DIR}
${CLANG_BOOTSTRAP_CMAKE_ARGS}
-DCMAKE_CXX_COMPILER=${CMAKE_BINARY_DIR}/bin/clang++
-DCMAKE_C_COMPILER=${CMAKE_BINARY_DIR}/bin/clang
+ -DCMAKE_ASM_COMPILER=${CMAKE_BINARY_DIR}/bin/clang
+ ${LTO_LIBRARY} ${LTO_AR} ${LTO_RANLIB}
INSTALL_COMMAND ""
STEP_TARGETS configure build
${cmake_3_4_USES_TERMINAL_OPTIONS}