lto.cmake
92b60da223b3chloride

lto.cmake
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			# Link time optimisation
			# =======================

			# Ref : https://lists.launchpad.net/kicad-developers/msg17900.html

			# The script need to find the GCC version of ar / nm / ranlib to access
			# the LTO plugin.
			# If they are not in PATH, their location can be given by the variable BINUTILS_DIR

			if( SPECMICP_LTO AND USE_LD_GOLD)
			# It's necessary to find the gcc/llvm ar/nm/ranlib because we need the lto plugin
			if ("${CMAKE_CXX_COMPILER_ID}" MATCHES "GNU")
			find_program( LTO_AR NAMES gcc-ar HINTS ${BINUTILS_DIR} )
			find_program( LTO_NM NAMES gcc-nm HINTS ${BINUTILS_DIR} )
			find_program( LTO_RANLIB NAMES gcc-ranlib HINTS ${BINUTILS_DIR} )
			set ( LTO_FLAGS " -flto -fno-fat-lto-objects")
			elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
			find_program( LTO_AR NAMES llvm-ar HINTS ${BINUTILS_DIR} )
			find_program( LTO_NM NAMES llvm-nm HINTS ${BINUTILS_DIR} )
			find_program( LTO_RANLIB NAMES llvm-ranlib HINTS ${BINUTILS_DIR} )
			set ( LTO_FLAGS " -flto")
			endif()


			if( LTO_AR AND LTO_NM AND LTO_RANLIB )
			set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${LTO_FLAGS}")
			# use correct programs
			set( CMAKE_AR "${LTO_AR}" )
			set( CMAKE_NM "${LTO_NM}" )
			set( CMAKE_RANLIB "${LTO_RANLIB}" )
			else()
			message( WARNING "Binutils wrappers with LTO plugin could not be found. Disabling LTO." )
			endif()

			mark_as_advanced(
			LTO_AR
			LTO_NM
			LTO_RANLIB
			LTO_FLAGS
			)
			endif()