CMake 3.4 Release Notes

Contents

• CMake 3.4 Release Notes
  • New Features
    • Generators
    • Commands
    • Variables
    • Properties
    • Modules
    • Generator Expressions
    • CTest
    • CPack
    • Other
  • Deprecated and Removed Features
  • Other Changes

Changes made since CMake 3.3 include the following.

New Features

Generators

• The Visual Studio 14 2015 generator learned to select a Windows 10 SDK based on the value of the CMAKE_SYSTEM_VERSION variable and the SDKs available on the host.
• CMake learned rudimentary support for the Apple Swift language. When using the Xcode generator with Xcode 6.1 or higher, one may enable the Swift language with the enable_language() command or the project() command (this is an error with other generators or when Xcode is too old). Then one may list .swift source files in targets for compilation.

Commands

• The find_program() command learned a NAMES_PER_DIR option to consider all given NAMES in each directory before moving on to the next directory.
• The get_filename_component() command learned a new BASE_DIR subcommand. This is used to specify a base directory when calculating an absolute path from a relative path.
• The if() command learned a new TEST operator that evaluates to true if a given test name has been defined by the add_test() command. See policy CMP0064.
• The install(DIRECTORY) command DESTINATION option learned to support generator expressions.
• The install(FILES) command DESTINATION option learned to support generator expressions.
• The string() command learned a new APPEND subcommand.

Variables

• The Makefile Generators and the Ninja generator learned to add compiler launcher tools like distcc and ccache along with the compiler for C and CXX languages. See the CMAKE_<LANG>_COMPILER_LAUNCHER variable and <LANG>_COMPILER_LAUNCHER target property for details.
• New CMAKE_LINK_SEARCH_START_STATIC and CMAKE_LINK_SEARCH_END_STATIC variables were introduced to initialize the LINK_SEARCH_START_STATIC and LINK_SEARCH_END_STATIC target properties, respectively.

Properties

• Visual Studio Generators learned to support additional target properties to customize projects for NVIDIA Nsight Tegra Visual Studio Edition:
  • ANDROID_ANT_ADDITIONAL_OPTIONS
  • ANDROID_ARCH
  • ANDROID_ASSETS_DIRECTORIES
  • ANDROID_JAR_DEPENDENCIES
  • ANDROID_JAR_DIRECTORIES
  • ANDROID_JAVA_SOURCE_DIR
  • ANDROID_NATIVE_LIB_DEPENDENCIES
  • ANDROID_NATIVE_LIB_DIRECTORIES
  • ANDROID_PROCESS_MAX
  • ANDROID_PROGUARD
  • ANDROID_PROGUARD_CONFIG_PATH
  • ANDROID_SECURE_PROPS_PATH
  • ANDROID_SKIP_ANT_STEP
  • ANDROID_STL_TYPE
• The ARCHIVE_OUTPUT_DIRECTORY, LIBRARY_OUTPUT_DIRECTORY, and RUNTIME_OUTPUT_DIRECTORY target properties learned to support generator expressions.
• The SOURCE_DIR and BINARY_DIR target properties were introduced to allow project code to query where a target is defined.
• The OUTPUT_NAME target property and its variants learned to support generator expressions.
• A TARGET_MESSAGES global property was added to tell the Makefile Generators whether to generate commands to print output after each target is completed.
• On Windows with MS-compatible tools, CMake learned to optionally generate a module definition (.def) file for SHARED libraries. See the WINDOWS_EXPORT_ALL_SYMBOLS target property.

Modules

• The ExternalProject module ExternalProject_Add() function GIT_SUBMODULES option now also limits the set of submodules that are initialized in addition to the prior behavior of limiting the set of submodules that are updated.
• The ExternalProject module learned new USES_TERMINAL arguments for giving steps exclusive terminal access. This is useful with the Ninja generator to monitor CMake superbuild progress and prevent CPU oversubscription.
• The FindBISON module BISON_TARGET macro learned a new DEFINES_FILE option to specify a custom output header to be generated.
• The FindHDF5 module learend a new HDF5_PREFER_PARALLEL option allowing users to specify that a parallel HDF5 tool is preferred if both are available.
• The FindIce module now provides imported targets.
• The FindJava module learned to optionally find the idlj and jarsigner tools.
• The FindOpenSSL module now provides imported targets.
• The FindOpenSSL module learned a new OPENSSL_USE_STATIC_LIBS option to search only for static libraries.
• The FindPkgConfig learned a new pkg_get_variable() command which may be used to query for arbitrary variables from a package (such as for related tools or data and plugin install paths).
• The FindProtobuf module gained a new protobuf_generate_python() function to generate python sources from .proto files.
• The FindTIFF module learned to search separately for debug and release variants.
• The FindwxWidgets module learned to support version requests.
• The FindXercesC module learned to search separately for debug and release variants.
• The FindZLIB module learned to search separately for debug and release variants.
• The GNUInstallDirs module learned special default values for certain installation prefixes according to the GNU Coding Standards and the Filesystem Hierarchy Standard.
• The UseJava module add_jar function learned to support response files (e.g. @srcs.txt) for source specification.
• The UseJava module install_jar function learned new DESTINATION and COMPONENT options to specify the corresponding install() command options.
• The UseJava module gained a new create_javah function to create C headers from Java classes.

Generator Expressions

• A new $<SHELL_PATH:...> generator expression has been added.

CTest

• CTest learned to optionally measure the CPU load during parallel testing and avoid starting tests that may cause the load to exceed a given threshold. See the ctest(1) command --test-load option, the TestLoad setting of the CTest Test Step, the CTEST_TEST_LOAD variable, and the TEST_LOAD option of the ctest_test() command.
• ctest(1) learned options --test-output-size-passed and --test-output-size-failed to customize the limit on test output size submitted when running as a Dashboard Client.

CPack

• The CPack DEB Generator learned to set package dependencies per component. See variables:
  • CPACK_DEBIAN_<COMPONENT>_PACKAGE_BREAKS
  • CPACK_DEBIAN_<COMPONENT>_PACKAGE_CONFLICTS
  • CPACK_DEBIAN_<COMPONENT>_PACKAGE_ENHANCES
  • CPACK_DEBIAN_<COMPONENT>_PACKAGE_PREDEPENDS
  • CPACK_DEBIAN_<COMPONENT>_PACKAGE_PROVIDES
  • CPACK_DEBIAN_<COMPONENT>_PACKAGE_RECOMMENDS
  • CPACK_DEBIAN_<COMPONENT>_PACKAGE_REPLACES
  • CPACK_DEBIAN_<COMPONENT>_PACKAGE_SUGGESTS
• The CPack module learned to package empty directories.
• The CPack module gained a new setting, CPACK_VERBATIM_VARIABLES, which can be used to ensure the cpack program receives the settings’ values exactly as they were set, even if they contain CMake-special characters. For compatibility, it’s off by default.

Other

• The Compile Features functionality is now aware of features supported by GNU C compilers on Windows.
• CMake learned to honor *.manifest source files with MSVC tools. Manifest files named as sources of .exe and .dll targets will be merged with linker-generated manifests and embedded in the binary.
• The Concurrent Fortran 77 compiler is now supported. Its compiler id is CCur.
• cmake(1) gained a new --trace-expand command line option that is like --trace but expands variable references in the output.

Deprecated and Removed Features

• The CMakeExpandImportedTargets module is now documented as deprecated. See module documentation for an explanation.
• The CMAKE_USE_RELATIVE_PATHS variable no longer has any effect. Previously it was partially implemented and unreliable.

Other Changes

• The CheckFunctionExists, CheckLibraryExists, CheckSymbolExists, and FindThreads modules learned to work in environments where only CXX is enabled.
• The CPack DEB Generator now correctly excludes symlinks during package checksum calculation.
• The CPack DEB Generator no longer uses fakeroot and system tar program for packaging.
• The CPack module no longer mangles settings with CMake-special characters when they’re used as defaults for other settings. The macro cpack_set_if_not_set, which was responsible for this, is now deprecated.
• CMake no longer links executables with flags to export symbols unless the ENABLE_EXPORTS target property is set. See policy CMP0065.
• The SONAME field is no longer set for MODULE libraries created with the add_library() command. MODULE libraries are meant for explicit dynamic loading at runtime. They cannot be linked so SONAME is not useful.
• The internal CMAKE_<LANG>_COMPILE_OBJECT rule variable now substitutes compiler include flags in a separate <INCLUDES> placeholder instead of the main <FLAGS> placeholder.