CMake 3.13 Release Notes
************************

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Changes made since CMake 3.12 include the following.

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

Generators
----------

* The :ref:`Visual Studio Generators` for VS 2010 and above learned to
  support the :prop_tgt:`INTERPROCEDURAL_OPTIMIZATION` target property
  and supporting :module:`CheckIPOSupported` module.

* The :generator:`Xcode` generator learned to configure more Xcode Scheme
  fields.  See the :variable:`CMAKE_XCODE_GENERATE_SCHEME` variable.

* The :generator:`Green Hills MULTI` generator has been updated:

  - Added support for architecture selection through
    :variable:`CMAKE_GENERATOR_PLATFORM`:
    e.g. ``arm``, ``ppc``, and ``86``.

  - Added support for toolset selection through
    :variable:`CMAKE_GENERATOR_TOOLSET`,
    e.g. ``comp_201205``, ``comp_201510``, ``comp_201722_beta``.

  - Added support for platform selection through ``GHS_TARGET_PLATFORM``,
    e.g. ``integrity``, ``linux``, ``standalone``, etc.

  - No longer checks that ``arm`` based compilers are installed but ensures
    that the correct ``gbuild.exe`` exists.

  - No longer hard-codes ARM files, BSP, toolset, or OS locations.

Command-Line
------------

* The :manual:`cmake(1)` command gained the ``-S <source_dir>``
  command line option to specify the location of the source directory.
  This option can be used independently of ``-B``.

* The :manual:`cmake(1)` command gained the ``-B <build_dir>``
  command line option to specify the location of the build directory.
  This option can be used independently of ``-S``.

* The :manual:`cmake(1)` ``-E create_symlink`` command can now be used
  on Windows.

Commands
--------

* The :command:`add_custom_command` and :command:`add_custom_target` commands
  learned to support generator expressions in ``WORKING_DIRECTORY`` options.

* The :command:`add_link_options` command was created to add link
  options in the current directory.

* The :command:`install(TARGETS)` command learned to install targets
  created outside the current directory.

* The :command:`link_directories` command gained options to control
  insertion position.

* The :command:`list(SORT)` command gained options to control the
  comparison operation used to order the entries.

* The :command:`math` command gained options for hexadecimal.

* The :command:`target_link_directories` command was created to
  specify link directories for targets and their dependents.

* The :command:`target_link_options` command was created to
  specify link options for targets and their dependents.

* The :command:`target_link_libraries` command may now be called
  to modify targets created outside the current directory.
  See policy :policy:`CMP0079`.

Variables
---------

* A :variable:`CMAKE_AUTOGEN_VERBOSE` variable was added to optionally
  increase the verbosity of :prop_tgt:`AUTOMOC`, :prop_tgt:`AUTOUIC`
  and :prop_tgt:`AUTORCC` from within CMake project code.

* A :variable:`CMAKE_VS_GLOBALS` variable was added to initialize
  :prop_tgt:`VS_GLOBAL_<variable>` target properties on targets as
  they are created.

Properties
----------

* The :prop_tgt:`DEPLOYMENT_ADDITIONAL_FILES` target property was
  added to tell the :generator:`Visual Studio 9 2008` generator
  to specify additional files for deployment to WinCE devices
  for remote debugging.

* The :prop_tgt:`INTERFACE_LINK_DEPENDS` target property was created
  to specify transitive link dependencies on files.

* The :prop_tgt:`LINK_DEPENDS` target property learned to support
  :manual:`generator expressions <cmake-generator-expressions(7)>`.

* :prop_tgt:`LINK_DIRECTORIES` and :prop_tgt:`INTERFACE_LINK_DIRECTORIES`
  target properties were added to collect link directories for a target
  and its dependents.  Use the :command:`target_link_directories` command
  to set them.

* :prop_tgt:`LINK_OPTIONS` and :prop_tgt:`INTERFACE_LINK_OPTIONS` target
  properties were added to collect link options for a target and its
  dependents.  Use the :command:`target_link_options` command to set them.

* A :prop_dir:`LINK_OPTIONS` directory property was added to collect
  link options for targets created under the current directory.
  Use the :command:`add_link_options` command to set it.

* A :prop_tgt:`STATIC_LIBRARY_OPTIONS` target property was created
  to specify archiver options to use when creating static libraries.

* A :prop_tgt:`VS_DEBUGGER_COMMAND_ARGUMENTS` target property was created to
  set the debugging command line arguments with
  :ref:`Visual Studio Generators` for VS 2010 and above.

* A :prop_tgt:`VS_DEBUGGER_ENVIRONMENT` target property was created to
  set the debugging environment with
  :ref:`Visual Studio Generators` for VS 2010 and above.

* The :prop_tgt:`VS_DEBUGGER_COMMAND` and
  :prop_tgt:`VS_DEBUGGER_WORKING_DIRECTORY` target properties
  now support generator expressions.

Modules
-------

* The :module:`FindBoost` module gained a ``Boost_ARCHITECTURE`` option
  to specify a Boost architecture-specific library filename fragment.

* The :module:`FindCURL` module learned to find debug and release variants
  separately.

* The :module:`FindMatlab` module gained new components ``ENGINE_LIBRARY`` and
  ``DATAARRAY_LIBRARY`` to request finding the Matlab C++ Engine and DataArray
  libraries respectively.

* The :module:`FindMatlab` module now explicitly exports mexFunction in Visual
  Studio.

* The :module:`FindMatlab` module gained a new ``MCC_COMPILER``
  component to request finding the Matlab Compiler add-on.

* The :module:`FindPkgConfig` module gained an option to create imported
  targets in global scope.

* The :module:`FindPkgConfig` module gained support for ``<`` and ``>``
  operators for version checks in addition to the already supported
  operators ``>=``, ``<=``, and ``=``.

* Modules :module:`FindPython3`, :module:`FindPython2` and :module:`FindPython`
  gain capability to control order of resource lookup on macOS (Framework) and
  Windows (Registry).

* The :module:`FindSubversion` module ``Subversion_WC_INFO`` command
  gained an ``IGNORE_SVN_FAILURE`` option to suppress failures,
  e.g. when the source tree is not under Subversion control.

* The :module:`UseSWIG` module learned to manage target property
  :prop_tgt:`INCLUDE_DIRECTORIES` for ``SWIG`` compilation.

CTest
-----

* :manual:`ctest(1)` gained a ``--progress`` option to enable a live
  test progress summary when output goes to a terminal.

CPack
-----

* The :cpack_gen:`CPack DEB Generator` learned to split debug symbols into
  a corresponding .ddeb package when ``CPACK_DEBIAN_DEBUGINFO_PACKAGE`` is
  set.

* The :cpack_gen:`CPack DEB Generator` learned to honor the ``SOURCE_DATE_EPOCH``
  environment variable when packaging files.  This is useful for generating
  reproducible packages.

* CPack gained a new :cpack_gen:`CPack External Generator` which is used to
  export the CPack metadata in a format that other software can understand. The
  intention of this generator is to allow external packaging software to take
  advantage of CPack's features when it may not be possible to use CPack for
  the entire packaging process.

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

* An explicit deprecation diagnostic was added for policies ``CMP0055``
  through ``CMP0063`` (``CMP0054`` and below were already deprecated).
  The :manual:`cmake-policies(7)` manual explains that the OLD behaviors
  of all policies are deprecated and that projects should port to the
  NEW behaviors.

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

* The precompiled binaries provided on ``cmake.org`` now include
  qthelp-format documentation.

* The :command:`option` command now honors an existing normal variable
  of the same name and does nothing instead of possibly creating a cache
  entry (or setting its type) and removing the normal variable.
  See policy :policy:`CMP0077`.

* The :ref:`Makefile Generators` learned to remove custom command and
  custom target byproducts during ``make clean``.

* The :command:`target_sources` command now interprets relative source file
  paths as relative to the current source directory.  This simplifies
  incrementally building up a target's sources from subdirectories.  The
  :policy:`CMP0076` policy was added to provide backward compatibility with
  the old behavior where required.

* The :module:`BundleUtilities` module may no longer be included at configure
  time. This was always a bug anyway. See policy :policy:`CMP0080`.

* The :module:`UseSWIG` module has changed strategy for target naming.
  See policy :policy:`CMP0078`.

* The :prop_tgt:`LINK_DIRECTORIES` target property now expects absolute paths.
  See policy :policy:`CMP0081`.

* The CPack generators have been moved into their own separate section
  in the documentation, rather than having the documentation in their
  internal implementation modules.
  These internal implementation modules are also no longer available
  to scripts that may have been incorrectly including them, because
  they should never have been available in the first place.

Updates
=======

Changes made since CMake 3.13.0 include the following.

3.13.2
------

* CMake 3.13.0 included a change to pass compiler implicit include
  directories to the ``moc`` tool for :prop_tgt:`AUTOMOC`.  This has
  been reverted due to regressing existing builds and will need
  further investigation before being re-introduced in a later release.

3.13.3
------

* The :generator:`Visual Studio 15 2017` generator has been fixed to work
  when VS 2019 is installed.

* CMake now checks that at least one of the source or binary directory
  is specified when running CMake and issues an error if both are missing.
  This has always been a documented requirement, but the implementation
  previously accidentally accepted cases in which neither are specified
  so long as some other argument is given, and silently used the current
  working directory as the source and build tree.

3.13.4
------

* The error added by 3.13.3 in cases that neither a source or binary
  directory is specified has been downgraded to a warning.  While this
  was never intended, documented, nor supported behavior, some projects
  relied on it.  The error has been downgraded to a warning for the
  remainder of the 3.13.x release series to allow a transition period,
  but it may become a fatal error again in a later release.  Scripts
  relying on the old behavior can be trivially fixed by specifying
  the path to the source tree (even if just ``.``) explicitly and
  continue to work with all versions of CMake.