Help: Organize and revise 3.18 release notes

Add section headers similar to the 3.18 release notes and move each
individual bullet into an appropriate section.  Revise a few bullets.

Help/release/3.18.rst

@@ -7,137 +7,168 @@ CMake 3.18 Release Notes
 
 Changes made since CMake 3.17 include the following.
 
-* :command:`add_library` and :command:`add_executable` gain the capability
-  to create an ``ALIAS`` to
-  non-``GLOBAL`` :ref:`Imported Target <Imported Targets>`.
+New Features
+============
 
-* Creation of an ``ALIAS`` target overwriting an existing target now raise an
-  error. See policy :policy:`CMP0107`.
+Languages
+---------
 
-* :manual:`ccmake(1)` learned to read a :envvar:`CCMAKE_COLORS`
-  environment variable to customize colors.
+* The ``CUDA`` language can now be compiled using Clang.
 
-* New :module:`CheckLinkerFlag` module has been added to provide a facility to
-  check validity of link flags.
+Command-Line
+------------
 
-* :manual:`cmake-gui(1)` now populates its generator selection
-  widget default value from the :envvar:`CMAKE_GENERATOR` environment
-  variable.  Additionally, environment variables
-  :envvar:`CMAKE_GENERATOR_PLATFORM` and :envvar:`CMAKE_GENERATOR_TOOLSET`
-  are used to populate their respective widget defaults.
+* :manual:`cmake(1)` gained support for profiling of CMake scripts through
+  the parameters ``--profiling-output`` and ``--profiling-format``.
 
-* The :command:`cmake_language()` command was added for meta-operations on
-  scripted or built-in commands, starting with a mode to ``CALL`` other
-  commands, and ``EVAL CODE`` to inplace evaluate a CMake script.
 * :manual:`cmake(1)` gained a ``cat`` command line
   option that can be used to concatenate files and print them
   on standard output.
 
-* The :cpack_gen:`CPack RPM Generator` gained
-  :variable:`CPACK_RPM_PRE_TRANS_SCRIPT_FILE`
-  :variable:`CPACK_RPM_POST_TRANS_SCRIPT_FILE`
-  variables to specify pre- and post-trans scripts.
+Commands
+--------
 
-* The :module:`CTestCoverageCollectGCOV` module
-  :command:`ctest_coverage_collect_gcov` function gained a
-  ``TARBALL_COMPRESSION`` option to control compression of the
-  tarball of collected results.
+* The :command:`add_library` and :command:`add_executable` commands
+  learned to create :ref:`Alias Targets` referencing non-``GLOBAL``
+  :ref:`Imported Targets`.
 
-* :manual:`ctest(1)` now logs environment variables that it sets for each test,
-  either due to the :prop_test:`ENVIRONMENT` property or the
-  :ref:`resource allocation <ctest-resource-allocation>` feature, and submits
-  this log to CDash. It does not log environment variables that were set
-  outside of CTest.
+* The :command:`cmake_language()` command was added for meta-operations on
+  scripted or built-in commands, starting with a mode to ``CALL`` other
+  commands, and ``EVAL CODE`` to inplace evaluate a CMake script.
 
-* :manual:`ctest(1)` gained a new :variable:`CTEST_RESOURCE_SPEC_FILE`
-  variable, which can be used to specify a
-  :ref:`resource specification file <ctest-resource-specification-file>`.
+* The :command:`execute_process` command gained the ``ECHO_OUTPUT_VARIABLE``
+  and ``ECHO_ERROR_VARIABLE`` options.
 
-* :manual:`ctest(1)` gained a ``--stop-on-failure`` option,
-  which can be used to stop running the tests once one has failed.
+* The :command:`export` command now raise an error if used multiple times with
+  same ``FILE`` without ``APPEND``. See policy :policy:`CMP0103`.
 
-* The :command:`ctest_test` command gained a ``STOP_ON_FAILURE`` option
-  which can be used to stop running the tests once one has failed.
+* The :command:`file` command gained the ``ARCHIVE_CREATE`` and
+  ``ARCHIVE_EXTRACT`` subcommands to expose the :manual:`cmake(1)` ``-E tar``
+  functionality to CMake scripting code.
+
+* The :command:`file(CONFIGURE)` subcommand was created in order to replicate
+  the :command:`configure_file` functionality without resorting to a
+  pre-existing file on disk as input. The content is instead passed as a
+  string.
+
+* The :command:`file(UPLOAD)` command gained ``TLS_VERIFY`` and ``TLS_CAINFO``
+  options to control server certificate verification.
+
+* The :command:`find_program`, :command:`find_library`, :command:`find_path`
+  and :command:`find_file` commands gained a new ``REQUIRED`` option that will
+  stop processing with an error message if nothing is found.
+
+* The :command:`get_property` command with ``SOURCE`` scope gained the
+  ``DIRECTORY`` and ``TARGET_DIRECTORY`` options to get a property
+  from the provided directory scope.
+
+* The :command:`get_source_file_property` command gained the ``DIRECTORY``
+  and ``TARGET_DIRECTORY`` options to get a property from the
+  provided directory scope.
+
+* The :command:`list` operation ``SORT`` gained the ``NATURAL`` sort
+  option to sort using natural order (see ``strverscmp(3)`` manual).
+
+* The :command:`set_property` command with the ``SOURCE`` scope gained the
+  ``DIRECTORY`` and ``TARGET_DIRECTORY`` options to set properties
+  in the provided directory scopes.
+
+* The :command:`set_source_files_properties` command gained the ``DIRECTORY``
+  and ``TARGET_DIRECTORY`` options to set properties in the provided
+  directory scopes.
 
-* :variable:`CMAKE_CUDA_ARCHITECTURES` is now initialized when
+* The :command:`string` command learned a new ``HEX`` sub-command, which
+  converts strings into their hexadecimal representation.
+
+Variables
+---------
+
+* A :variable:`CMAKE_CUDA_ARCHITECTURES` variable was added to specify
+  CUDA output architectures.  Users are encouraged to use this instead of
+  specifying options manually, as this approach is compiler-agnostic.
+  The variable is initialized automatically when
   :variable:`CMAKE_CUDA_COMPILER_ID <CMAKE_<LANG>_COMPILER_ID>` is ``NVIDIA``.
-  Empty :prop_tgt:`CUDA_ARCHITECTURES` raises an error. See policy
-  :policy:`CMP0104`.
+  The variable is used to initialize the new :prop_tgt:`CUDA_ARCHITECTURES`
+  target property.  See policy :policy:`CMP0104`.
 
-* Added :prop_tgt:`CUDA_ARCHITECTURES` target property for specifying CUDA
-  output architectures. Users are encouraged to use this instead of specifying
-  options manually, as this approach is compiler-agnostic.
+* The :variable:`CMAKE_PCH_WARN_INVALID` variable was added to initialize the
+  :prop_tgt:`PCH_WARN_INVALID` target property to allow the removal of the
+  precompiled header invalid warning.
 
-* The ``CUDA`` language now supports Clang as a compiler.
+Properties
+----------
 
-* When building CMake itself from source and not using a system-provided
-  libcurl, HTTP/2 support is now enabled for commands supporting
-  network communication via ``http(s)``, such as :command:`file(DOWNLOAD)`,
-  :command:`file(UPLOAD)`, and :command:`ctest_submit`.
-  The precompiled binaries provided on ``cmake.org`` now support HTTP/2.
+* The :prop_tgt:`CUDA_ARCHITECTURES` target property was added to specify
+  CUDA output architectures. Users are encouraged to use this instead of
+  specifying options manually, as this approach is compiler-agnostic.
+  The property is initialized by the new :variable:`CMAKE_CUDA_ARCHITECTURES`
+  variable.  See policy :policy:`CMP0104`.
 
-* The :module:`Documentation` module has been deprecated via
-  :policy:`CMP0106`. This module was essentially VTK code that CMake should
-  not be shipping anymore.
+* The :prop_tgt:`Fortran_PREPROCESS` target property and
+  :prop_sf:`Fortran_PREPROCESS` source-file property were added to
+  control preprocessing of Fortran source files.
 
-* An explicit deprecation diagnostic was added for policy ``CMP0070``
-  and policy ``CMP0071`` (``CMP0069`` 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.
+* The :prop_tgt:`FRAMEWORK_MULTI_CONFIG_POSTFIX_<CONFIG>` target property
+  and associated :variable:`CMAKE_FRAMEWORK_MULTI_CONFIG_POSTFIX_<CONFIG>`
+  variable were created to allow adding a postfix to the name of a
+  framework file name when using a multi-config generator.
 
-* the :prop_tgt:`LINK_OPTIONS` and :prop_tgt:`INTERFACE_LINK_OPTIONS` target
-  properties are now used for the device link step. See policy :policy:`CMP0105`.
+* The :prop_sf:`OBJECT_OUTPUTS` source file property now supports
+  :manual:`generator expressions <cmake-generator-expressions(7)>`.
 
-* The :command:`execute_process` command gained the ``ECHO_OUTPUT_VARIABLE``
-  and ``ECHO_ERROR_VARIABLE`` options.
+* The :prop_tgt:`UNITY_BUILD_MODE` target property was added to tell
+  generators which algorithm to use for grouping included source
+  files.
 
-* The :command:`export` command now raise an error if used multiple times with
-  same ``FILE`` without ``APPEND``. See policy :policy:`CMP0103`.
+* The :prop_tgt:`VS_SOURCE_SETTINGS_<tool>` target property was added
+  to tell :ref:`Visual Studio Generators` for VS 2010 and above to add
+  metadata to non-built source files using ``<tool>``.
 
-* The :command:`ExternalProject_Add` command gained a new
-  ``GIT_REMOTE_UPDATE_STRATEGY`` keyword.  This can be used to specify how
-  failed rebase operations during a git update should be handled.
-  The ``CMAKE_EP_GIT_REMOTE_UPDATE_STRATEGY`` variable was also added as a
-  global default and is honored by both the :module:`ExternalProject` and
-  :module:`FetchContent` modules.
+* The :prop_sf:`VS_SETTINGS` source file property was added to tell
+  :ref:`Visual Studio Generators` for VS 2010 and above to add
+  metadata to a non-built source file.
 
-* The :command:`FetchContent_Declare` command now supports a ``SOURCE_SUBDIR``
-  option.  It can be used to direct :command:`FetchContent_MakeAvailable`
-  to look in a different location for the ``CMakeLists.txt`` file.
+* The :prop_tgt:`VS_PLATFORM_TOOLSET` target property was added to tell
+  :ref:`Visual Studio Generators` for VS 2010 and above to override
+  the platform toolset.
 
-* The :command:`file` command gained the ``ARCHIVE_{CREATE|EXTRACT}`` subcommands.
+* The :prop_tgt:`VS_SOLUTION_DEPLOY` target property was added to tell
+  :ref:`Visual Studio Generators` for VS 2010 and above to mark a
+  target for deployment even when not building for Windows Phone/Store/CE.
 
-  These subcommands will replicate the :manual:`cmake(1)` ``-E tar`` functionality in
-  CMake scripting code.
+Modules
+-------
 
-* The :command:`file(CONFIGURE)` subcommand was created in order replicate the
-  :command:`configure_file` functionality without resorting to a pre-existing
-  file on disk as input. The content is instead passed as a string.
+* The :module:`CheckLinkerFlag` module has been added to provide a
+  facility to check validity of link flags.
 
-* The :command:`file(UPLOAD)` command gained ``TLS_VERIFY`` and ``TLS_CAINFO``
-  options to control server certificate verification.
+* The :module:`ExternalProject` module :command:`ExternalProject_Add` command
+  gained a new ``GIT_REMOTE_UPDATE_STRATEGY`` keyword.  This can be used to
+  specify how failed rebase operations during a git update should be handled.
+  The ``CMAKE_EP_GIT_REMOTE_UPDATE_STRATEGY`` variable was also added as a
+  global default and is honored by both the :module:`ExternalProject` and
+  :module:`FetchContent` modules.
+
+* The :module:`FetchContent` module :command:`FetchContent_Declare` command
+  now supports a ``SOURCE_SUBDIR`` option.  It can be used to direct
+  :command:`FetchContent_MakeAvailable` to look in a different location
+  for the ``CMakeLists.txt`` file.
 
 * The :module:`FindBLAS` module now provides an imported target.
 
 * The :module:`FindLAPACK` module now provides an imported target.
 
 * The :module:`FindPython3`, :module:`FindPython2` and :module:`FindPython`
-  modules gained the possibility to create artifacts cache variables for
-  interactive edition.
+  modules:
 
-* The :module:`FindPython3`, :module:`FindPython2` and :module:`FindPython`
-  modules gained sub-components ``Development.Module`` and
-  ``Development.Embed`` for ``Development`` component.
+  * gained the possibility to create per-artifact cache variables for
+    interactive editing in :manual:`cmake-gui(1)` and :manual:`ccmake(1)`.
 
-* The :module:`FindPython3`, :module:`FindPython2` and :module:`FindPython`
-  modules gained the capability to specify which implementations to search for.
-
-* The :module:`FindPython3`, :module:`FindPython2` and :module:`FindPython`
-  modules support now the ``IronPython`` implementation on all platforms.
+  * gained sub-components ``Development.Module`` and
+    ``Development.Embed`` under the ``Development`` component.
 
-* The :module:`FindPython3`, :module:`FindPython2` and :module:`FindPython`
-  modules gained the capability to handle ``PyPy`` product.
+  * gained the capability to specify which Python implementations to find,
+    including ``IronPython`` and ``PyPy``.
 
 * The :module:`FindRuby` module input and output variables were all renamed
   from ``RUBY_`` to ``Ruby_`` for consistency with other find modules.
@@ -147,112 +178,123 @@ Changes made since CMake 3.17 include the following.
 * The :module:`FindSWIG` module now accepts target languages as  ``COMPONENTS``
   and ``OPTIONAL_COMPONENTS`` arguments to ``find_package``.
 
-* The :prop_tgt:`Fortran_PREPROCESS` target property and
-  :prop_sf:`Fortran_PREPROCESS` source-file property were added to
-  control preprocessing of Fortran source files.
+* The :module:`GoogleTest` module :command:`gtest_discover_tests` command:
 
-* The :module:`FindPackageHandleStandardArgs` module option ``REQUIRED_VARS``
-  is now optional if ``HANDLE_COMPONENTS`` is specified.
+  * gained a new ``DISCOVERY_MODE`` option to control when the test
+    discovery step is run.  It offers a new ``PRE_TEST`` setting to
+    run the discovery at test time instead of build time.
 
-* The :prop_tgt:`FRAMEWORK_MULTI_CONFIG_POSTFIX_<CONFIG>` target property
-  and associated :variable:`CMAKE_FRAMEWORK_MULTI_CONFIG_POSTFIX_<CONFIG>`
-  variable were created to allow adding a postfix to the name of a
-  framework file name when using a multi-config generator.
+  * gained a new optional parameter ``XML_OUTPUT_DIR``. When set the
+    JUnit XML test results are stored in that directory.
 
-* To manage device and host link steps, the ``$<DEVICE_LINK:...>`` and
-  ``$<HOST_LINK:...>``
-  :manual:`generator expressions <cmake-generator-expressions(7)>` were added.
+* The :module:`FindLibXslt` module now provides imported targets.
+
+* The :module:`UseSWIG` module now supports Fortran as a target language if
+  the ``SWIG_EXECUTABLE`` is SWIG-Fortran_.
+
+.. _`SWIG-Fortran`: https://github.com/swig-fortran/swig
+
+Generator Expressions
+---------------------
+
+* The ``$<DEVICE_LINK:...>`` and ``$<HOST_LINK:...>``
+  :manual:`generator expressions <cmake-generator-expressions(7)>` were added
+  to manage device and host link steps.
 
 * The ``$<LINK_LANGUAGE:...>`` and ``$<LINK_LANG_AND_ID:...>``
   :manual:`generator expressions <cmake-generator-expressions(7)>` were added.
 
-* :prop_sf:`OBJECT_OUTPUTS` now support :manual:`generator expressions <cmake-generator-expressions(7)>`.
+CTest
+-----
 
-* The :module:`GoogleTest` module :command:`gtest_discover_tests` command
-  gained a new ``DISCOVERY_MODE`` option to control when the test
-  discovery step is run.  It offers a new ``PRE_TEST`` setting to
-  run the discovery at test time instead of build time.
+* :manual:`ctest(1)` gained a new :variable:`CTEST_RESOURCE_SPEC_FILE`
+  variable, which can be used to specify a
+  :ref:`resource specification file <ctest-resource-specification-file>`.
 
-* The :module:`GoogleTest` module :command:`gtest_discover_tests` command
-  gained a new optional parameter ``XML_OUTPUT_DIR``. When set the JUnit XML
-  test results are stored in that directory.
+* :manual:`ctest(1)` gained a ``--stop-on-failure`` option,
+  which can be used to stop running the tests once one has failed.
 
-* The :prop_tgt:`UNITY_BUILD_MODE` target property was added to tell
-  generators which algorithm to use for grouping included source
-  files.
+* The :command:`ctest_test` command gained a ``STOP_ON_FAILURE`` option
+  which can be used to stop running the tests once one has failed.
 
-* The :module:`FindLibXslt` module now provides imported targets.
+* The :module:`CTestCoverageCollectGCOV` module
+  :command:`ctest_coverage_collect_gcov` command gained a
+  ``TARBALL_COMPRESSION`` option to control compression of the
+  tarball of collected results.
 
-* The :command:`list` operation ``SORT`` gained the ``NATURAL`` sort
-  option to sort using natural order (see ``strverscmp(3)`` manual).
+CPack
+-----
 
-* On Windows, the :generator:`Ninja` and :generator:`Ninja Multi-Config`
-  generators, when a compiler is not explicitly specified, now select
-  the first compiler (of any name) found in directories listed by the
-  ``PATH`` environment variable.
+* The :cpack_gen:`CPack Archive Generator`'s ``TXZ`` format learned the
+  :variable:`CPACK_ARCHIVE_THREADS` variable to enable parallel compression.
+  Requires support in the ``liblzma`` used by CMake.
 
 * The :cpack_gen:`CPack NSIS Generator` gained a new variable
   :variable:`CPACK_NSIS_MANIFEST_DPI_AWARE` to declare that the
   installer is DPI-aware.
 
-* The :cpack_gen:`CPack Archive Generator`'s ``TXZ`` format learned the
-  :variable:`CPACK_ARCHIVE_THREADS` variable to enable parallel compression.
-  Requires support in the ``liblzma`` used by CMake.
+* The :cpack_gen:`CPack RPM Generator` gained
+  :variable:`CPACK_RPM_PRE_TRANS_SCRIPT_FILE`
+  :variable:`CPACK_RPM_POST_TRANS_SCRIPT_FILE`
+  variables to specify pre- and post-trans scripts.
 
-* The :variable:`CMAKE_PCH_WARN_INVALID` variable was added to initialize the
-  :prop_tgt:`PCH_WARN_INVALID` target property to allow the removal of the
-  precompiled header invalid warning.
+Other
+-----
 
-* Add support for profiling of CMake scripts through the parameters
-  ``--profiling-output`` and ``--profiling-format``. These options can
-  be used by users to gain insight into the performance of their scripts.
+* :manual:`cmake-gui(1)` now populates its generator selection
+  widget default value from the :envvar:`CMAKE_GENERATOR` environment
+  variable.  Additionally, environment variables
+  :envvar:`CMAKE_GENERATOR_PLATFORM` and :envvar:`CMAKE_GENERATOR_TOOLSET`
+  are used to populate their respective widget defaults.
 
-  The first supported output format is ``google-trace`` which is a format
-  supported by Google Chrome's ``about:tracing`` tab.
+* :manual:`ccmake(1)` learned to read a :envvar:`CCMAKE_COLORS`
+  environment variable to customize colors.
 
-* The :command:`find_program`, :command:`find_library`, :command:`find_path`
-  and :command:`find_file` commands gained a new ``REQUIRED`` option that will
-  stop processing with an error message if nothing is found.
+Deprecated and Removed Features
+===============================
 
-* Linking a target to itself through an alias now raise an error.
-  See policy :policy:`CMP0108`.
+* The :module:`Documentation` module has been deprecated via
+  :policy:`CMP0106`. This module was essentially VTK code that CMake should
+  not be shipping anymore.
 
-* The :command:`set_property` with the ``SOURCE`` scope gained the
-  ``DIRECTORY`` and ``TARGET_DIRECTORY`` options to set properties
-  in the provided directory scopes.
-* The :command:`set_source_files_properties` gained the ``DIRECTORY``
-  and ``TARGET_DIRECTORY`` options to set properties in the provided
-  directory scopes.
-* The :command:`get_property` with ``SOURCE`` scope gained the
-  ``DIRECTORY`` and ``TARGET_DIRECTORY`` options to get a property
-  from the provided directory scope.
-* The :command:`get_source_file_property` gained the ``DIRECTORY``
-  and ``TARGET_DIRECTORY`` options to get a property from the
-  provided directory scope.
+* An explicit deprecation diagnostic was added for policy ``CMP0070``
+  and policy ``CMP0071`` (``CMP0069`` 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.
 
-* The :command:`source_group` command now also recognizes forward slashes
-  as subgroup delimiters, not just backslashes.
+Other Changes
+=============
 
-* The :command:`string` command learned a new ``HEX`` sub-command, which
-  converts strings into their hexadecimal representation.
+* On Windows, the :generator:`Ninja` and :generator:`Ninja Multi-Config`
+  generators, when a compiler is not explicitly specified, now select
+  the first compiler (of any name) found in directories listed by the
+  ``PATH`` environment variable.
 
-* The :module:`UseSWIG` module now supports Fortran as a target language if
-  the ``SWIG_EXECUTABLE`` is SWIG-Fortran_.
+* The :prop_tgt:`LINK_OPTIONS` and :prop_tgt:`INTERFACE_LINK_OPTIONS` target
+  properties are now used for the device link step.
+  See policy :policy:`CMP0105`.
 
-.. _`SWIG-Fortran`: https://github.com/swig-fortran/swig
+* Creation of an ``ALIAS`` target overwriting an existing target now raises an
+  error. See policy :policy:`CMP0107`.
 
-* The :prop_tgt:`VS_SOURCE_SETTINGS_<tool>` target property was added
-  to tell :ref:`Visual Studio Generators` for VS 2010 and above to add
-  metadata to non-built source files using ``<tool>``.
+* Linking a target to itself through an alias now raises an error.
+  See policy :policy:`CMP0108`.
 
-* The :prop_sf:`VS_SETTINGS` source file property was added to tell
-  :ref:`Visual Studio Generators` for VS 2010 and above to add
-  metadata to a non-built source file.
+* The :module:`FindPackageHandleStandardArgs` module option ``REQUIRED_VARS``
+  is now optional if ``HANDLE_COMPONENTS`` is specified.
 
-* The :prop_tgt:`VS_PLATFORM_TOOLSET` target property was added to tell
-  :ref:`Visual Studio Generators` for VS 2010 and above to override
-  the platform toolset.
+* The :command:`source_group` command now also recognizes forward slashes
+  as subgroup delimiters, not just backslashes.
 
-* The :prop_tgt:`VS_SOLUTION_DEPLOY` target property was added to tell
-  :ref:`Visual Studio Generators` for VS 2010 and above to mark a
-  target for deployment even when not building for Windows Phone/Store/CE.
+* :manual:`ctest(1)` now logs environment variables that it sets for each test,
+  either due to the :prop_test:`ENVIRONMENT` property or the
+  :ref:`resource allocation <ctest-resource-allocation>` feature, and submits
+  this log to CDash. It does not log environment variables that were set
+  outside of CTest.
+
+* When building CMake itself from source and not using a system-provided
+  libcurl, HTTP/2 support is now enabled for commands supporting
+  network communication via ``http(s)``, such as :command:`file(DOWNLOAD)`,
+  :command:`file(UPLOAD)`, and :command:`ctest_submit`.
+  The precompiled binaries provided on ``cmake.org`` now support HTTP/2.