cmake_minimum_required(VERSION 3.8) project(CheckIPOSupported-CXX LANGUAGES CXX) cmake_policy(SET CMP0069 NEW) include(CheckIPOSupported) check_ipo_supported(RESULT ipo_supported OUTPUT ipo_output) if(ipo_supported) set(CMAKE_INTERPROCEDURAL_OPTIMIZATION TRUE) elseif(CMake_TEST_IPO_WORKS_CXX) string(REPLACE "\n" "\n " ipo_output "${ipo_output}") message(FATAL_ERROR "IPO expected to work, but the check failed:\n ${ipo_output}") endif() add_library(foo STATIC foo.cpp) if(NOT CYGWIN AND (NOT WIN32 OR "x${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")) add_library(bar SHARED bar.cpp) if(WIN32) # Bindexplib for clang supports LTO objects set_target_properties(bar PROPERTIES WINDOWS_EXPORT_ALL_SYMBOLS ON) endif() else() # TODO: bindexplib doesn't support exporting IPO symbols with other compilers on Windows add_library(bar STATIC bar.cpp) endif() add_executable(CheckIPOSupported-CXX main.cpp) target_link_libraries(CheckIPOSupported-CXX PUBLIC foo bar) enable_testing() add_test(NAME CheckIPOSupported-CXX COMMAND CheckIPOSupported-CXX)