sfizz/cmake/CheckIPO.cmake

# Added in CMake 3.9

if (CMAKE_VERSION VERSION_LESS 3.9)
    message (WARNING "\nIPO checks are only available on CMake 3.9 and later.")

    set(ENABLE_LTO OFF CACHE BOOL "" FORCE)

    function (SFIZZ_ENABLE_LTO_IF_NEEDED TARGET)
    endfunction()

    return()
endif()

include (CheckIPOSupported)
check_ipo_supported (RESULT result OUTPUT output)

if (CMAKE_SYSTEM_PROCESSOR STREQUAL armv7l)
    set(ENABLE_LTO OFF CACHE BOOL "" FORCE)
endif()

if (result AND ENABLE_LTO AND CMAKE_BUILD_TYPE STREQUAL "Release")
    message (STATUS "\nLTO enabled.")
else()
    if (${output})
        message (WARNING "\nIPO disabled: ${output}")
    else()
        message (WARNING "\nIPO was disabled or not in a Release build.")
    endif()
    set(ENABLE_LTO OFF CACHE BOOL "" FORCE)
endif()

function (SFIZZ_ENABLE_LTO_IF_NEEDED TARGET)
    if (${ENABLE_LTO})
        message(STATUS "Enabling LTO on ${TARGET}")
        set_property (TARGET ${TARGET} PROPERTY INTERPROCEDURAL_OPTIMIZATION True)
    endif()
endfunction()