CMake 3.9 Release Notes¶
Changes made since CMake 3.8 include the following.
New Features¶
Languages¶
- CUDAis now supported by the Visual Studio Generators for VS 2010 and above. This complements the existing support by the Makefile Generators and the- Ninjagenerator. CUDA 8.0.61 or higher is recommended due to known bugs in the VS integration by earlier versions.
- CMake is now aware of the - C++ standardsand- C standardsand their associated meta-features for the following- compiler ids:- Cray,- PGI, and- XL.
Generators¶
- Visual Studio Generators for VS 2010 and above learned to support the - ASM_NASMlanguage when- nasmis installed.
- The - Xcodegenerator learned to create Xcode schema files. This is an experimental feature and can be activated by setting the- CMAKE_XCODE_GENERATE_SCHEMEvariable to a- TRUEvalue.
Commands¶
- The - add_library()command- IMPORTEDoption learned to support Object Libraries.
- The - find_library()command learned to search- libx32paths when the build targets the- x32ABI. See the- FIND_LIBRARY_USE_LIBX32_PATHSglobal property.
- The - include_external_msproject()command learned to use the- MAP_IMPORTED_CONFIG_<CONFIG>target property to map current configurations to the external configurations.
- The - install(TARGETS)command learned a new- OBJECTSoption to specify where to install Object Libraries.
- The - install(EXPORT)command learned how to export Object Libraries.
- The - project()command learned an optional- DESCRIPTIONparameter to set the- PROJECT_DESCRIPTIONvariable.
- The - separate_arguments()command gained a- NATIVE_COMMANDmode that performs argument separation depending on the host operating system.
Variables¶
- A - CMAKE_ANDROID_NDK_DEPRECATED_HEADERSvariable was added for use when Cross Compiling for Android with the NDK to request use of the deprecated headers even when unified headers are available. The default is now to use unified headers if available.
- A - CMAKE_AUTOMOC_DEPEND_FILTERSvariable was introduced to allow- CMAKE_AUTOMOCto extract additional dependency file names for- mocfrom the contents of source files.
- A - CMAKE_AUTOUIC_SEARCH_PATHSvariable was introduced to allow- CMAKE_AUTOUICto search for- foo.uiin more places than the vicinity of the file including- ui_foo.h.
- A - CMAKE_FIND_LIBRARY_CUSTOM_LIB_SUFFIXvariable was added to tell the- find_library()command to search in a- lib<suffix>directory before each- libdirectory that would normally be searched.
- A - CMAKE_INTERPROCEDURAL_OPTIMIZATIONvariable was added to initialize the- INTERPROCEDURAL_OPTIMIZATIONproperty on all targets.
- A - CMAKE_<LANG>_COMPILER_ARvariable was added to hold the path to the GCC/Clang wrapper of- ar.
- A - CMAKE_<LANG>_COMPILER_RANLIBvariable was added to hold the path to the GCC/Clang wrapper of- ranlib.
- The - CMAKE_SYSROOT_COMPILEand- CMAKE_SYSROOT_LINKvariables were added to use separate sysroots for compiling and linking.
Properties¶
- A new - AUTOGEN_BUILD_DIRtarget property was introduced to set a custom output directory for- AUTOMOC,- AUTOUIC, and- AUTORCC.
- A new - AUTOMOC_DEPEND_FILTERStarget property was introduced to allow- AUTOMOCto extract additional dependency file names for- mocfrom the contents of source files.
- A new - AUTOUIC_SEARCH_PATHStarget property was introduced to allow- AUTOUICto search for- foo.uiin more places than the vicinity of the file including- ui_foo.h.
- Global properties - AUTOGEN_SOURCE_GROUP,- AUTOMOC_SOURCE_GROUPand- AUTORCC_SOURCE_GROUPwere introduced to allow files generated by- AUTOMOCor- AUTORCCto be placed in a- source_group().
- A - BUILD_WITH_INSTALL_NAME_DIRtarget property and corresponding- CMAKE_BUILD_WITH_INSTALL_NAME_DIRvariable were added to control whether to use the- INSTALL_NAME_DIRtarget property value for binaries in the build tree. This is for macOS- install_nameas- BUILD_WITH_INSTALL_RPATHis for- RPATH.
- A - CUDA_PTX_COMPILATIONtarget property was added to Object Libraries to support compiling to- .ptxfiles instead of host object files.
- A - GENERATOR_IS_MULTI_CONFIGglobal property was added to determine whether the current generator is a multi-configuration generator (such as Visual Studio Generators or- Xcode).
- The - INTERPROCEDURAL_OPTIMIZATIONtarget property is now enforced when enabled. CMake will add IPO flags unconditionally or produce an error if it does not know the flags for the current compiler. The project is now responsible to use the- CheckIPOSupportedmodule to check for IPO support before enabling the target property. See policy- CMP0069.
- The - WINDOWS_EXPORT_ALL_SYMBOLStarget property may now be used in combination with explicit- .deffiles in order to export all symbols from the object files within a target plus an explicit list of symbols that the linker finds in dependencies (e.g.- msvcrt.lib).
Modules¶
- A - CheckIPOSupportedmodule was added to help projects check whether interprocedural optimization (IPO) is supported by the current toolchain and CMake version.
- The - CMakeFindDependencyMacromodule- find_dependencymacro now forwards all arguments to the underlying- find_package()call. Existing uses will continue to function as before, but callers can now access the full suite of arguments that- find_package()accepts.
- The - FeatureSummarymodule- feature_summary()command now accepts the new- DEFAULT_DESCRIPTIONoption that will print the default title for the selected package type.
- The - FeatureSummarymodule gained a new- FeatureSummary_<TYPE>_DESCRIPTIONvariable that can be defined for each- <TYPE>to replace the type name with the specified string whenever the package type is used in an output string by the module.
- The - FindDoxygenmodule learned to control Doxygen behavior using CMake variables and generate documentation via the newly added- doxygen_add_docs()function. The Doxygen input file (- Doxyfile) is automatically generated and doxygen is run as part of a custom target. Additional components can be specified to find optional tools:- dot,- mscgenand- dia.
- The - FindMPImodule now provides imported targets.
- The - FindProtobufmodule- protobuf_generate_cpp()command gained an- EXPORT_MACROoption to specify the name of a DLL export markup macro.
- The - FindProtobufmodule now supports usage of static libraries for Unix via a new- Protobuf_USE_STATIC_LIBSinput variable.
- The - FindProtobufmodule now provides imported targets when the libraries are found.
- A new - GoogleTestmodule was added to provide the- gtest_add_tests()function independently of the- FindGTestmodule. The function was also updated to support keyword arguments, with functionality expanded to allow a test name prefix and suffix to be specified, the dependency on the source files to be optional and the list of discovered test cases to be returned to the caller.
CTest¶
- The - ctest_submit()command gained a- HTTPHEADERoption to specify custom headers to send during submission.
- The - ctest(1)executable gained new options which allow the developer to disable automatically adding tests to the test set to satisfy fixture dependencies.- -FSprevents adding setup tests for fixtures matching the provided regular expression,- -FCprevents adding cleanup tests for matching fixtures and- -FAprevents adding any test for matching fixtures.
- A - DISABLEDtest property was added to mark tests that are configured but explicitly disabled so they do not run.
CPack¶
- The - CPack Archive Generatorlearned to modify the filename per-component. See the- CPACK_ARCHIVE_FILE_NAMEvariable and its per-component version- CPACK_ARCHIVE_<component>_FILE_NAME.
- The - CPackComponentmodule- cpack_add_component()command gained a new- PLIST <filename>option to specify the- pkgbuild- --component-plistargument when using the- productbuildgenerator.
- The - CPackIFWmodule- cpack_ifw_configure_component()and- cpack_ifw_configure_component_group()commands gained internationalization support for- DISPLAY_NAMEand- DESCRIPTIONoptions.
- The - CPack IFW Generatorlearned the new hint- CPACK_IFW_ROOTvariable for finding the QtIFW tool suite installed in a non-standard place.
- The - CPack productbuild Generatorgained a new- CPACK_PRODUCTBUILD_RESOURCES_DIRvariable to specify resources to be copied into the- Resourcesdirectory.
- The - CPack RPM Generatorlearned to modify the- debuginfopackage name. See the- CPACK_RPM_DEBUGINFO_FILE_NAMEvariable.
- The - CPack WIX Generatorpatching system now has the ability to set additional attributes. This can be done by specifying attributes with the- CPackWiXFragmentXML tag after the- Idattribute. See the- CPACK_WIX_PATCH_FILEvariable.
- The - CPack WIX Generatorimplemented a new- CPACK_WIX_ROOT_FOLDER_IDvariable which allows using a custom root folder ID instead of the default- ProgramFilesFolder/- ProgramFiles64Folder.
Other¶
- Interprocedural optimization (IPO) is now supported for GNU and Clang compilers using link time optimization (LTO) flags. See the - INTERPROCEDURAL_OPTIMIZATIONtarget property and- CheckIPOSupportedmodule.
- The - TARGET_OBJECTS- generator expressionis now supported by the- add_custom_command()and- file(GENERATE)commands.
- Two new informational generator expressions to retrieve Apple Bundle directories have been added. The first one - $<TARGET_BUNDLE_DIR:tgt>outputs the full path to the Bundle directory, the other one- $<TARGET_BUNDLE_CONTENT_DIR:tgt>outputs the full path to the- Contentsdirectory of macOS Bundles and App Bundles. For all other bundle types and SDKs it is identical with- $<TARGET_BUNDLE_DIR:tgt>. The new expressions are helpful to query Bundle locations independent of the different Bundle types and layouts on macOS and iOS.
Deprecated and Removed Features¶
- An explicit deprecation diagnostic was added for policies - CMP0036and below. The- cmake-policies(7)manual explains that the OLD behaviors of all policies are deprecated and that projects should always port to the NEW behaviors as soon as possible.
- The - Visual Studio 8 2005generator is now deprecated and will be removed in a future version of CMake.
- The - Visual Studio 7 .NET 2003generator has been removed.
- The - Xcodegenerator dropped support for Xcode versions older than 3.
- The - FindDoxygenmodule has deprecated several variables.
- The version of curl bundled with CMake no longer accepts URLs of the form - file://c:/...on Windows due to a change in upstream curl 7.52. Use the form- file:///c:/...instead to work on all versions.
Other Changes¶
- When using - AUTOMOC, CMake now scans for the presence of the- Q_PLUGIN_METADATAmacro and reruns moc when the file from the macro's- FILEargument changes.
- When - AUTOMOCdetects an include statement of the form- #include "moc_<basename>.cpp"the search for the respective header file now looks in the- INCLUDE_DIRECTORIESof the target as well.
- When running tests, CTest learned to treat skipped tests (using the - SKIP_RETURN_CODEproperty) the same as tests with the new- DISABLEDproperty. Due to this change, CTest will not indicate failure when all tests are either skipped or pass.
- The - Ninjagenerator has loosened the dependencies of object compilation. Object compilation now depends only on custom targets and custom commands associated with libraries on which the object's target depends and no longer depends on the libraries themselves. Source files in dependent targets may now compile without waiting for their targets' dependencies to link.
- On macOS, - RPATHsettings such as- BUILD_WITH_INSTALL_RPATHno longer affect the- install_namefield. See policy- CMP0068.
- The - Visual Studio 14 2015generator has been taught about a change to the- v140toolset made by a VS 2015 update. VS changed the set of values it understands for the- GenerateDebugInformationlinker setting that produces the- -DEBUGlinker flag variants.
Updates¶
Changes made since CMake 3.9.0 include the following.
3.9.1¶
- The - find_command- PACKAGE_ROOTsearch path group added by CMake 3.9.0 has been removed for the 3.9 series due to regressions caused by new use of- <PackageName>_ROOTvariables. The behavior may be re-introduced in the future in a more-compatible way.
3.9.2¶
- On macOS, the default application bundle - Info.plistfile no longer enables Hi-DPI support as it did in 3.9.0 and 3.9.1. The change had to be reverted because it broke iOS applications.
- The Xcode generator no longer adds "outputPaths" to custom script build phases as it did in 3.9.0 and 3.9.1. This was added in an attempt to support Xcode 9's new build system, but broke incremental rebuilds for both the old and new Xcode build systems. 
