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63 lines
1.8 KiB
CMake
63 lines
1.8 KiB
CMake
# - Compile and run code to check for C++ features
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#
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# This functions compiles a source file under the `cmake` folder
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# and adds the corresponding `HAVE_[FILENAME]` flag to the CMake
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# environment
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#
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# cxx_feature_check(<FLAG> [<VARIANT>])
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#
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# - Example
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#
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# include(CXXFeatureCheck)
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# cxx_feature_check(STD_REGEX)
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# Requires CMake 2.8.12+
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if(__cxx_feature_check)
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return()
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endif()
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set(__cxx_feature_check INCLUDED)
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function(cxx_feature_check FILE)
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string(TOLOWER ${FILE} FILE)
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string(TOUPPER ${FILE} VAR)
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string(TOUPPER "HAVE_${VAR}" FEATURE)
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if (DEFINED HAVE_${VAR})
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set(HAVE_${VAR} 1 PARENT_SCOPE)
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add_definitions(-DHAVE_${VAR})
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return()
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endif()
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message("-- Performing Test ${FEATURE}")
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if(CMAKE_CROSSCOMPILING)
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try_compile(COMPILE_${FEATURE}
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${CMAKE_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/cmake/${FILE}.cpp
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CMAKE_FLAGS ${BENCHMARK_CXX_LINKER_FLAGS}
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LINK_LIBRARIES ${BENCHMARK_CXX_LIBRARIES})
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if(COMPILE_${FEATURE})
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message(WARNING
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"If you see build failures due to cross compilation, try setting HAVE_${VAR} to 0")
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set(RUN_${FEATURE} 0)
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else()
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set(RUN_${FEATURE} 1)
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endif()
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else()
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message("-- Performing Test ${FEATURE}")
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try_run(RUN_${FEATURE} COMPILE_${FEATURE}
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${CMAKE_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/cmake/${FILE}.cpp
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CMAKE_FLAGS ${BENCHMARK_CXX_LINKER_FLAGS}
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LINK_LIBRARIES ${BENCHMARK_CXX_LIBRARIES})
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endif()
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if(RUN_${FEATURE} EQUAL 0)
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message("-- Performing Test ${FEATURE} -- success")
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set(HAVE_${VAR} 1 PARENT_SCOPE)
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add_definitions(-DHAVE_${VAR})
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else()
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if(NOT COMPILE_${FEATURE})
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message("-- Performing Test ${FEATURE} -- failed to compile")
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else()
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message("-- Performing Test ${FEATURE} -- compiled but failed to run")
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endif()
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endif()
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endfunction()
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