From 8170f7a37747c3a414b8ad45bb587adcdac6e0da Mon Sep 17 00:00:00 2001 From: Tomi Valkeinen Date: Wed, 28 Sep 2016 10:42:03 +0300 Subject: Improve LTO detection code Split LTO detection into separate func and file, and create a cached LTO_WORKS variable. Signed-off-by: Tomi Valkeinen Reviewed-by: Laurent Pinchart --- LTO.cmake | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 LTO.cmake (limited to 'LTO.cmake') diff --git a/LTO.cmake b/LTO.cmake new file mode 100644 index 0000000..9a18d77 --- /dev/null +++ b/LTO.cmake @@ -0,0 +1,32 @@ +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() -- cgit v1.2.3