CMake/Help/release/3.6.rst

CMake 3.6 Release Notes
***********************

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Changes made since CMake 3.5 include the following.

New Features
============

Generators
----------

* The :generator:`Ninja` generator learned to produce phony targets
  of the form ``sub/dir/all`` to drive the build of a subdirectory.
  This is equivalent to ``cd sub/dir; make all`` with
  :ref:`Makefile Generators`.

* The :generator:`Ninja` generator now includes system header files in build
  dependencies to ensure correct re-builds when system packages are updated.

* The :generator:`Visual Studio 14 2015` generator learned to support the
  Clang/C2 toolsets, e.g. with the ``-T v140_clang_3_7`` option.
  This feature is experimental.

Commands
--------

* The :command:`add_custom_command` and :command:`add_custom_target` commands
  learned how to use the :prop_tgt:`CROSSCOMPILING_EMULATOR` executable
  target property.

* The :command:`install` command learned a new ``EXCLUDE_FROM_ALL`` option
  to leave installation rules out of the default installation.

* The :command:`list` command gained a ``FILTER`` sub-command to filter
  list elements by regular expression.

* The :command:`string(TIMESTAMP)` and :command:`file(TIMESTAMP)`
  commands gained support for the ``%s`` placeholder.  This is
  the number of seconds since the UNIX Epoch.

* The :command:`try_compile` command source file signature now honors
  configuration-specific flags (e.g. :variable:`CMAKE_<LANG>_FLAGS_DEBUG`)
  in the generated test project.  Previously only the default such flags
  for the current toolchain were used.

Variables
---------

* A :variable:`CMAKE_DEPENDS_IN_PROJECT_ONLY` variable was introduced
  to tell :ref:`Makefile Generators` to limit dependency scanning only
  to files in the project source and build trees.

* A new :variable:`CMAKE_HOST_SOLARIS` variable was introduced to
  indicate when CMake is running on an Oracle Solaris host.

* A :variable:`CMAKE_<LANG>_STANDARD_INCLUDE_DIRECTORIES` variable was
  added for use by toolchain files to specify system include directories
  to be appended to all compiler command lines.

* The :variable:`CMAKE_<LANG>_STANDARD_LIBRARIES` variable is now documented.
  It is intended for use by toolchain files to specify system libraries to be
  added to all linker command lines.

* A :variable:`CMAKE_NINJA_OUTPUT_PATH_PREFIX` variable was introduced
  to tell the :generator:`Ninja` generator to configure the generated
  ``build.ninja`` file for use as a ``subninja``.

* A :variable:`CMAKE_TRY_COMPILE_PLATFORM_VARIABLES` variable was
  added for use by toolchain files to specify platform-specific
  variables that must be propagated by the :command:`try_compile`
  command into test projects.

* A :variable:`CMAKE_TRY_COMPILE_TARGET_TYPE` variable was added
  to optionally tell the :command:`try_compile` command to build
  a static library instead of an executable.  This is useful for
  cross-compiling toolchains that cannot link binaries without
  custom flags or scripts.

Properties
----------

* A :prop_tgt:`DEPLOYMENT_REMOTE_DIRECTORY` target property was introduced
  to tell the :generator:`Visual Studio 9 2008` and
  :generator:`Visual Studio 8 2005` generators to generate the "remote
  directory" for WinCE project deployment and debugger settings.

* A :prop_tgt:`<LANG>_CLANG_TIDY` target property and supporting
  :variable:`CMAKE_<LANG>_CLANG_TIDY` variable were introduced to tell the
  :ref:`Makefile Generators` and the :generator:`Ninja` generator to run
  ``clang-tidy`` along with the compiler for ``C`` and ``CXX`` languages.

* A :prop_test:`TIMEOUT_AFTER_MATCH` test property was introduced to
  optionally tell CTest to enforce a secondary timeout after matching
  certain output from a test.

* A :prop_tgt:`VS_CONFIGURATION_TYPE` target property was introduced
  to specify a custom project file type for :ref:`Visual Studio Generators`
  supporting VS 2010 and above.

* A :prop_dir:`VS_STARTUP_PROJECT` directory property was introduced
  to specify for :ref:`Visual Studio Generators` the default startup
  project for generated solutions (``.sln`` files).

Modules
-------

* The :module:`CMakePushCheckState` module now pushes/pops/resets the variable
  ``CMAKE_EXTRA_INCLUDE_FILE`` used in :module:`CheckTypeSize`.

* The :module:`ExternalProject` module leared the ``GIT_SHALLOW 1``
  option to perform a shallow clone of a Git repository.

* The :module:`ExternalProject` module learned to initialize Git submodules
  recursively and also to initialize new submodules on updates.  Use the
  ``GIT_SUBMODULES`` option to restrict which submodules are initalized and
  updated.

* The :module:`ExternalProject` module leared the ``DOWNLOAD_NO_EXTRACT 1``
  argument to skip extracting the file that is downloaded (e.g., for
  self-extracting shell installers or ``.msi`` files).

* The :module:`ExternalProject` module now uses ``TLS_VERIFY`` when fetching
  from git repositories.

* The :module:`FindBLAS` and :module:`FindLAPACK` modules learned to
  support `OpenBLAS <http://www.openblas.net>`__.

* The :module:`FindCUDA` module learned to find the ``cublas_device`` library.

* The :module:`FindGTest` module ``gtest_add_tests`` function now causes
  CMake to automatically re-run when test sources change so that they
  can be re-scanned.

* The :module:`FindLTTngUST` module was introduced to find the LTTng-UST
  library.

* The :module:`FindPkgConfig` module learned to optionally create imported
  targets for the libraries it has found.

* The :module:`FindProtobuf` module learned to provide a ``Protobuf_VERSION``
  variable and check the version number requested in a :command:`find_package`
  call.

* The :module:`InstallRequiredSystemLibraries` module learned a new
  ``CMAKE_INSTALL_UCRT_LIBRARIES`` option to enable app-local deployment
  of the Windows Universal CRT libraries with Visual Studio 2015.

Platforms
---------

* The Clang compiler is now supported on CYGWIN.

* Support was added for the Bruce C Compiler with compiler id ``Bruce``.

CTest
-----

* The :command:`ctest_update` command now looks at the
  :variable:`CTEST_GIT_INIT_SUBMODULES` variable to determine whether
  submodules should be updated or not before updating.

* The :command:`ctest_update` command will now synchronize submodules on an
  update. Updates which add submodules or change a submodule's URL will now be
  pulled properly.

CPack
-----

* The :module:`CPackDeb` module learned how to handle ``$ORIGIN``
  in ``CMAKE_INSTALL_RPATH`` when :variable:`CPACK_DEBIAN_PACKAGE_SHLIBDEPS`
  is used for dependency auto detection.

* The :module:`CPackDeb` module learned how to generate ``DEBIAN/shlibs``
  contorl file when package contains shared libraries.

* The :module:`CPackDeb` module learned how to generate ``DEBIAN/postinst`` and
  ``DEBIAN/postrm`` files if the package installs libraries in
  ldconfig-controlled locations (e.g. ``/lib/``, ``/usr/lib/``).

* The :module:`CPackDeb` module learned how to generate dependencies between
  Debian packages if multi-component setup is used and
  :variable:`CPACK_COMPONENT_<compName>_DEPENDS` variables are set.
  For backward compatibility this feature is disabled by default.
  See :variable:`CPACK_DEBIAN_ENABLE_COMPONENT_DEPENDS`.

* The :module:`CPackDeb` module learned how to set custom package file names
  including how to generate properly-named Debian packages::

    <PackageName>_<VersionNumber>-<DebianRevisionNumber>_<DebianArchitecture>.deb

  For backward compatibility this feature is disabled by default. See
  :variable:`CPACK_DEBIAN_FILE_NAME` and
  :variable:`CPACK_DEBIAN_<COMPONENT>_FILE_NAME`.

* The :module:`CPackDeb` module learned how to set the package release number
  (``DebianRevisionNumber`` in package file name when used in combination with
  ``DEB-DEFAULT`` value set by :variable:`CPACK_DEBIAN_FILE_NAME`).  See
  :variable:`CPACK_DEBIAN_PACKAGE_RELEASE`.

* The :module:`CPackDeb` module learned how to set the package architecture
  per-component.  See :variable:`CPACK_DEBIAN_<COMPONENT>_PACKAGE_ARCHITECTURE`.

* The :module:`CPackDMG` module learned a new option to tell the CPack
  ``DragNDrop`` generaor to skip the ``/Applications`` symlink.
  See the :variable:`CPACK_DMG_DISABLE_APPLICATIONS_SYMLINK` variable.

* The :module:`CPackIFW` module gained a new
  :command:`cpack_ifw_update_repository` command to update a QtIFW-specific
  repository from a remote repository.

* The :module:`CPackRPM` module learned how to set RPM ``dist`` tag as part of
  RPM ``Release:`` tag when enabled (mandatory on some Linux distributions for
  e.g. on Fedora).
  See :variable:`CPACK_RPM_PACKAGE_RELEASE_DIST`.

* The :module:`CPackRPM` module learned how to set default values for owning
  user/group and file/directory permissions of package content.
  See :variable:`CPACK_RPM_DEFAULT_USER`, :variable:`CPACK_RPM_DEFAULT_GROUP`,
  :variable:`CPACK_RPM_DEFAULT_FILE_PERMISSIONS`,
  :variable:`CPACK_RPM_DEFAULT_DIR_PERMISSIONS` and their per component
  counterparts.

* The :module:`CPackRPM` module learned how to set user defined package file
  names, how to specify that rpmbuild should decide on file name format as
  well as handling of multiple rpm packages generated by a single user defined
  spec file.
  See :variable:`CPACK_RPM_PACKAGE_NAME` and
  :variable:`CPACK_RPM_<component>_PACKAGE_NAME`.

* The :module:`CPackRPM` module learned how to correctly handle symlinks
  that are pointing outside generated packages.

Other
-----

* The :manual:`Compile Features <cmake-compile-features(7)>` functionality
  is now aware of features supported by Intel C++ compilers versions 12.1
  through 16.0 on UNIX platforms.

Deprecated and Removed Features
===============================

* The :module:`CMakeForceCompiler` module and its macros are now deprecated.
  See module documentation for an explanation.

* The :command:`find_library`, :command:`find_path`, and :command:`find_file`
  commands no longer search in installation prefixes derived from the ``PATH``
  environment variable on non-Windows platforms.  This behavior was added in
  CMake 3.3 to support Windows hosts but has proven problematic on UNIX hosts.
  Users that keep some ``<prefix>/bin`` directories in the ``PATH`` just for
  their tools do not necessarily want any supporting ``<prefix>/lib``
  directories searched.  One may set the ``CMAKE_PREFIX_PATH`` environment
  variable with a :ref:`;-list <CMake Language Lists>` of prefixes that are
  to be searched.

* The :generator:`Visual Studio 7 .NET 2003` generator is now
  deprecated and will be removed in a future version of CMake.

* The :generator:`Visual Studio 7` generator (for VS .NET 2002) has been
  removed.  It had been deprecated since CMake 3.3.

* The :generator:`Visual Studio 6` generator has been removed.
  It had been deprecated since CMake 3.3.

Other Changes
=============

* The precompiled OS X binary provided on ``cmake.org`` now requires
  OS X 10.7 or newer.

* On Linux and FreeBSD platforms, when building CMake itself from source and
  not using a system-provided libcurl, OpenSSL is now used by default if it is
  found on the system.  This enables SSL/TLS support for commands supporting
  network communication via ``https``, such as :command:`file(DOWNLOAD)`,
  :command:`file(UPLOAD)`, and :command:`ctest_submit`.

* The :manual:`cmake(1)` ``--build`` command-line tool now rejects multiple
  ``--target`` options with an error instead of silently ignoring all but the
  last one.

* :prop_tgt:`AUTOMOC` now diagnoses name collisions when multiple source
  files in different directories use ``#include <moc_foo.cpp>`` with the
  same name (because the generated ``moc_foo.cpp`` files would collide).

* The :module:`FindBISON` module ``BISON_TARGET`` macro now supports
  special characters by passing the ``VERBATIM`` option to internal
  :command:`add_custom_command` calls.  This may break clients that
  added escaping manually to work around the bug.

* The :module:`FindFLEX` module ``FLEX_TARGET`` macro now supports
  special characters by passing the ``VERBATIM`` option to internal
  :command:`add_custom_command` calls.  This may break clients that
  added escaping manually to work around the bug.

* The :module:`FindProtobuf` module input and output variables were all renamed
  from ``PROTOBUF_`` to ``Protobuf_`` for consistency with other find modules.
  Input variables of the old case will be honored if provided, and output
  variables of the old case are always provided.

* The :module:`CPackRPM` module now supports upper cased component
  names in per component CPackRPM specific variables.
  E.g. component named ``foo`` now expects component specific
  variable to be ``CPACK_RPM_FOO_PACKAGE_NAME`` while before
  it expected ``CPACK_RPM_foo_PACKAGE_NAME``.
  Upper cased component name part in variables is compatible
  with convention used for other CPack variables.
  For back compatibility old format of variables is still valid
  and preferred if both versions of variable are set, but the
  preferred future use is upper cased component names in variables.
  New variables that will be added to CPackRPM in later versions
  will only support upper cased component variable format.