| function(check_lto) |
| if (DEFINED LTO_WORKS) |
| return() |
| endif() |
| |
| set(LTO_WORKS FALSE CACHE INTERNAL "LTO works") |
| |
| CHECK_CXX_COMPILER_FLAG("-flto" HAS_LTO_FLAG) |
| |
| if (NOT HAS_LTO_FLAG) |
| return() |
| endif() |
| |
| find_program(LTO_AR NAMES "${CMAKE_C_COMPILER}-ar" gcc-ar) |
| find_program(LTO_RANLIB NAMES "${CMAKE_C_COMPILER}-ranlib" gcc-ranlib) |
| |
| if (NOT LTO_AR OR NOT LTO_RANLIB) |
| return() |
| endif() |
| |
| EXECUTE_PROCESS(COMMAND "${LTO_AR}" --version RESULT_VARIABLE ret OUTPUT_QUIET ERROR_QUIET) |
| if (ret) |
| return() |
| endif() |
| |
| EXECUTE_PROCESS(COMMAND "${LTO_RANLIB}" --version RESULT_VARIABLE ret OUTPUT_QUIET ERROR_QUIET) |
| if (ret) |
| return() |
| endif() |
| |
| set(LTO_WORKS TRUE CACHE INTERNAL "LTO works") |
| endfunction() |
