Help: Consolidate 3.21 release notes

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Help/release/3.21.rst

+CMake 3.21 Release Notes
+************************
+
+.. only:: html
+
+  .. contents::
+
+Changes made since CMake 3.20 include the following.
+
+* The :command:`add_custom_command` command ``DEPFILE`` option learned to
+  support :manual:`generator expressions <cmake-generator-expressions(7)>`.
+
+* The :command:`add_custom_command` command gained ``DEPFILE`` support on
+  the :generator:`Xcode` generator, and on :ref:`Visual Studio Generators`
+  for VS 2012 and above.
+
+* The :ref:`add_custom_command(TARGET) <add_custom_command(TARGET)>` command
+  gained support for resolving target-dependent generator expressions.
+
+* ``ARMClang`` cpu/arch compile and link flags are no longer added
+  automatically based on the :variable:`CMAKE_SYSTEM_PROCESSOR`
+  variable or the undocumented ``CMAKE_SYSTEM_ARCH`` variable.
+  They must be specified explicitly.  See policy :policy:`CMP0123`.
+
+* The :manual:`cmake(1)` ``-E capabilities`` output now contains for each
+  generator a ``supportedPlatforms`` field listing platform known to
+  be supported in :variable:`CMAKE_GENERATOR_PLATFORM`.
+
+* The :manual:`cmake(1)` command gained the ``--install-prefix <dir>``
+  command line option to specify the location of the install prefix.
+
+* :manual:`cmake-presets(7)` configure preset gained support for specifying
+  the install prefix.
+
+* :manual:`cmake-presets(7)` now support conditional enabling of presets.
+
+* :manual:`cmake-presets(7)` gained support for a new ``${hostSystemName}``
+  macro.
+
+* :manual:`cmake-presets(7)` now support omitting the ``generator`` and
+  ``binaryDir`` fields.
+
+* :variable:`CMAKE_HOST_SYSTEM_NAME`'s undocumented version-stripping behavior
+  has been moved earlier, before :command:`project` or
+  :command:`enable_language` is called.
+* :variable:`CMAKE_SYSTEM_NAME`'s undocumented version-stripping behavior has
+  been removed entirely. If it is set by a ``-D`` flag or by a
+  :manual:`toolchain file <cmake-toolchains(7)>`, it is left unaltered, even if
+  it still contains a version number.
+
+* The :manual:`cmake(1)` command gained the ``--toolchain <path/to/file>``
+  command line option to specify a toolchain file.
+
+* The :ref:`Visual Studio Generators` for VS 2010 and above now place
+  per-source preprocessor definitions after target-wide preprocssor
+  definitions.  This makes VS consistent with the :ref:`Ninja Generators`
+  and the :ref:`Makefile Generators`.
+
+* The :cpack_gen:`CPack DragNDrop Generator` gained option
+  :variable:`CPACK_DMG_FILESYSTEM` to control the ``.dmg`` filesystem.
+
+* The new :variable:`CPACK_CUSTOM_INSTALL_VARIABLES`
+  can be used to set variables in CPack ``cmake_install.cmake``
+  invocations.
+
+* The :cpack_gen:`CPack NSIS Generator` gained a new variable
+  :variable:`CPACK_NSIS_EXECUTABLE` to specify the makensis
+  executable to use instead of the default one.
+
+* :prop_tgt:`C_STANDARD` and the
+  :manual:`Compile Features <cmake-compile-features(7)>` functionality gained
+  support for C17 and C23.
+
+* :manual:`ctest(1)` gained documentation for its ability to capture
+  :ref:`Additional Test Measurements`.
+
+* :manual:`ctest(1)` gained a ``--output-junit`` option to write test results
+  to a JUnit XML file.
+
+* :manual:`ctest(1)` learned to recognize files attached to a test at run time.
+  Previously it was only possible to attach files to tests at configure time
+  by using the :prop_test:`ATTACHED_FILES` or
+  :prop_test:`ATTACHED_FILES_ON_FAIL` test properties.
+  See :ref:`Additional Test Measurements` for more information.
+
+* Source file extensions ``.ixx`` and ``.cppm`` are now treated as C++.
+
+* The :prop_dir:`IMPORTED_TARGETS` directory property was added to
+  get a list of :ref:`Imported Targets` created in the current
+  directory.
+
+* The :envvar:`CMAKE_TOOLCHAIN_FILE` environment variable was added to
+  provide a default value for the :variable:`CMAKE_TOOLCHAIN_FILE` variable.
+
+* The :manual:`cmake-file-api(7)` "codemodel" version 2 ``version`` field has
+  component been updated to 2.3.
+
+* The :manual:`cmake-file-api(7)` "codemodel" version 2 gained a
+  new "directory" object containing directory-level information.
+  This includes a list of installers generated by the :command:`install`
+  command.
+
+* The :command:`file(COPY_FILE)` command was added to copy a file to another.
+
+* The :command:`file(REAL_PATH)` command gained the option ``EXPAND_TILDE`` to
+  replace any leading tilde with the path to the user's home directory.
+
+* The :command:`file(RENAME)` command learned to optionally capture
+  failure in a result variable.  It also gained a ``NO_REPLACE``
+  option to fail if the destination exists.
+
+* The :module:`FindDevIL` module now provides imported targets.
+
+* The :module:`FindIconv` module now has version support.
+
+* The :module:`FindIntl` module now has version support.
+
+* The :command:`find_file`, :command:`find_path`, :command:`find_program`,
+  and :command:`find_library` commands handle cache variables in the same way
+  regardless how they are defined. See policy :policy:`CMP0125` for details.
+
+* The :command:`find_file`, :command:`find_path`, :command:`find_program`,
+  and :command:`find_library` commands gained the option ``NO_CACHE`` to store
+  find result in normal variable.
+
+* The :module:`FindMsys` module was added to find MSYS installations.
+  Like :module:`FindCygwin`, it is used automatically by some other
+  find modules to locate UNIX-style tools on Windows.
+
+* The :module:`FindVulkan` module gained imported targets
+  ``Vulkan::Headers`` and ``Vulkan::glslangValidator``.
+
+* The :command:`foreach` command restrict loop variables to the loop scope.
+  See policy :policy:`CMP0124` for details.
+
+* Addition of the ``Fujitsu`` compiler ID operating in traditional ``Trad``
+  mode and ``FujitsuClang`` operating in ``Clang`` mode.
+* The :module:`FindOpenMP` module learned to support ``Fujitsu`` and
+  ``FujitsuClang``.
+* The :module:`FindMPI` module learned to support ``Fujitsu`` and
+  ``FujitsuClang`` in both host and cross compiling modes.
+* The :module:`FindBLAS` and :module:`FindLAPACK` modules learned to support
+  the serial ``Fujitsu SSL2`` and parallel ``Fujitsu SSL2BLAMP`` libraries.
+
+* The :command:`build_command` command gained a ``PARALLEL_LEVEL`` option.
+
+* The :command:`ctest_build` command gained a ``PARALLEL_LEVEL`` option.
+
+* The :command:`file(GET_RUNTIME_DEPENDENCIES)` command gained new
+  ``POST_INCLUDE_FILES`` and ``POST_EXCLUDE_FILES`` arguments.
+
+* CMake learned to support ``HIP`` as a first-class language that can be
+  enabled via the :command:`project` and :command:`enable_language` commands.
+
+* Names given as ``DEPENDS`` or ``DEPENDENCIES`` arguments to
+  :command:`cpack_ifw_configure_component` or
+  :command:`cpack_ifw_configure_component_group` may now contain hyphens.
+  This requires QtIFW 3.1 or later.
+
+* The :command:`install` command gained a new ``IMPORTED_RUNTIME_ARTIFACTS``
+  mode, which can be used to install the runtime artifacts of imported targets.
+
+* The :command:`install(TARGETS)` command gained new ``RUNTIME_DEPENDENCIES``
+  and ``RUNTIME_DEPENDENCY_SET`` arguments, which can be used to install
+  runtime dependencies using :command:`file(GET_RUNTIME_DEPENDENCIES)`.
+* The :command:`install` command gained a new ``RUNTIME_DEPENDENCY_SET`` mode,
+  which can be used to install runtime dependencies using
+  :command:`file(GET_RUNTIME_DEPENDENCIES)`.
+
+* The :command:`install(SCRIPT|CODE)` command
+  supports a new option ``ALL_COMPONENTS`` which allows
+  the corresponding code to run for every component of
+  a per component installation.
+
+* The :ref:`Makefile Generators` and the :generator:`Ninja` generator learned to
+  add linker launcher tools along with the linker for ``C``, ``CXX``, ``OBJC``, and
+  ``OBJCXX`` languages. See the :variable:`CMAKE_<LANG>_LINKER_LAUNCHER` variable
+  and :prop_tgt:`<LANG>_LINKER_LAUNCHER` target property for details.
+
+* :command:`target_link_libraries` calls referencing object libraries
+  via the :genex:`TARGET_OBJECTS` generator expression now place the
+  object files before all libraries on the link line, regardless of
+  their specified order.  See documentation on
+  :ref:`Linking Object Libraries via \$\<TARGET_OBJECTS\>` for details.
+
+* The :command:`list` command's ``GET``, ``INSERT``, ``SUBLIST``, and
+  ``REMOVE_AT`` subcommands now error with invalid (i.e., non-integer) values
+  are given as any of their index arguments based on the setting of policy
+  :policy:`CMP0121`.
+
+* The precompiled binaries provided on
+  `cmake.org <https://cmake.org/download/>`_ now support
+  ``liblzma`` multi-threading.  See the :variable:`CPACK_THREADS` and
+  :variable:`CPACK_ARCHIVE_THREADS` variables.
+
+* Messages printed to a terminal now may be colored by message type.
+
+* CMake now supports the MSYS runtime environment, much like CYGWIN.
+
+* The :ref:`Ninja Generators` now pass source files and include directories
+  to the compiler using absolute paths.  This makes diagnostic messages and
+  debug symbols more consistent, and matches the :ref:`Makefile Generators`.
+
+* The :generator:`NMake Makefiles` generator now encodes the generated
+  makefiles as UTF-8 with a BOM when using ``nmake`` from VS 9 or above.
+
+* :prop_tgt:`OBJC_STANDARD` gained support for C17 and C23.
+
+* :command:`project` now sets variables :variable:`PROJECT_IS_TOP_LEVEL` and
+  :variable:`<PROJECT-NAME>_IS_TOP_LEVEL` to indicate whether it was called
+  in a top level ``CMakeLists.txt`` file.
+
+* A new :genex:`TARGET_RUNTIME_DLLS` generator expression was added.
+
+* The :command:`set(CACHE)` command no longer removes a normal variable of the
+  same name, if any. See policy :policy:`CMP0126`.
+
+* The :module:`UseJava` module command ``add_jar`` gained option RESOURCES
+  allow explicit naming of resources with non-optional namespace.
+
+* The :module:`UseSWIG` module use now standard library name conventions for
+  ``CSharp`` language. See policy :policy:`CMP0122`.
+
+* :module:`UseSWIG` module gained the capability, for
+  :generator:`Xcode` generator, to use `swig` tool to generate implicit
+  dependencies.
+
+* The :prop_tgt:`XCODE_EMBED_APP_EXTENSIONS <XCODE_EMBED_<type>>` target property
+  was added to tell the :generator:`Xcode` generator to embed app extensions
+  such as iMessage sticker packs.
+  Aspects of the embedding can be customized with the
+  :prop_tgt:`XCODE_EMBED_APP_EXTENSIONS_PATH <XCODE_EMBED_<type>>`,
+  :prop_tgt:`XCODE_EMBED_APP_EXTENSIONS_CODE_SIGN_ON_COPY <XCODE_EMBED_<type>_CODE_SIGN_ON_COPY>` and
+  :prop_tgt:`XCODE_EMBED_APP_EXTENSIONS_REMOVE_HEADERS_ON_COPY <XCODE_EMBED_<type>_REMOVE_HEADERS_ON_COPY>`
+  properties.

Help/release/dev/ARMClang-cpu-arch-flags.rst

-ARMClang-cpu-arch-flags
------------------------
-
-* ``ARMClang`` cpu/arch compile and link flags are no longer added
-  automatically based on the :variable:`CMAKE_SYSTEM_PROCESSOR`
-  variable or the undocumented ``CMAKE_SYSTEM_ARCH`` variable.
-  They must be specified explicitly.  See policy :policy:`CMP0123`.

Help/release/dev/FindDevIL-imported-targets.rst

-FindDevIL
----------
-
-* The :module:`FindDevIL` module now provides imported targets.

Help/release/dev/FindIconv-version.rst

-FindIconv-version
------------------
-
-* The :module:`FindIconv` module now has version support.

Help/release/dev/FindIntl-version.rst

-FindIntl-version
-----------------
-
-* The :module:`FindIntl` module now has version support.

Help/release/dev/FindMsys.rst

-FindMsys
---------
-
-* The :module:`FindMsys` module was added to find MSYS installations.
-  Like :module:`FindCygwin`, it is used automatically by some other
-  find modules to locate UNIX-style tools on Windows.

Help/release/dev/FindVulkan-add-Headers-glslangValidator-targets.rst

-FindVulkan-add-Headers-glslangValidator-targets
------------------------------------------------
-
-* The :module:`FindVulkan` module gained imported targets
-  ``Vulkan::Headers`` and ``Vulkan::glslangValidator``.

Help/release/dev/UseJava-RESOURCES-NAMESPACE.rst

-UseJava-RESOURCES-NAMESPACE
----------------------------
-
-* The :module:`UseJava` module command ``add_jar`` gained option RESOURCES
-  allow explicit naming of resources with non-optional namespace.

Help/release/dev/UseSWIG-csharp.rst

-UseSWIG-csharp
---------------
-
-* The :module:`UseSWIG` module use now standard library name conventions for
-  ``CSharp`` language. See policy :policy:`CMP0122`.

Help/release/dev/UseSWIG-dependencies.rst

-UseSWIG-dependencies
---------------------
-
-* :module:`UseSWIG` module gained the capability, for
-  :generator:`Xcode` generator, to use `swig` tool to generate implicit
-  dependencies.

Help/release/dev/add_custom_command-DEPFILE-genex.rst

-add_custom_command-DEPFILE-genex
---------------------------------
-
-* The :command:`add_custom_command` command ``DEPFILE`` option learned to
-  support :manual:`generator expressions <cmake-generator-expressions(7)>`.

Help/release/dev/add_custom_command-DEPFILE.rst

-add_custom_command-DEPFILE
---------------------------
-
-* The :command:`add_custom_command` command gained ``DEPFILE`` support on
-  the :generator:`Xcode` generator, and on :ref:`Visual Studio Generators`
-  for VS 2012 and above.

Help/release/dev/add_custom_command-TARGET-genex.rst

-add_custom_command-TARGET-genex
--------------------------------
-
-* The :ref:`add_custom_command(TARGET) <add_custom_command(TARGET)>` command
-  gained support for resolving target-dependent generator expressions.

Help/release/dev/c-std.rst

-c-std
------
-
-* :prop_tgt:`C_STANDARD` and the
-  :manual:`Compile Features <cmake-compile-features(7)>` functionality gained
-  support for C17 and C23.

Help/release/dev/capabilties-generator-platforms.rst

-capabilties-generator-platforms
--------------------------------
-
-* The :manual:`cmake(1)` ``-E capabilities`` output now contains for each
-  generator a ``supportedPlatforms`` field listing platform known to
-  be supported in :variable:`CMAKE_GENERATOR_PLATFORM`.

Help/release/dev/cmake-install-prefix-command.rst

-cmake-install-prefix-command
-----------------------------
-
-* The :manual:`cmake(1)` command gained the ``--install-prefix <dir>``
-  command line option to specify the location of the install prefix.
-
-* :manual:`cmake-presets(7)` configure preset gained support for specifying
-  the install prefix.

Help/release/dev/cmake-presets-condition.rst

-cmake-presets-condition
------------------------
-
-* :manual:`cmake-presets(7)` now support conditional enabling of presets.

Help/release/dev/cmake-presets-host-system-name.rst

-cmake-presets-host-system-name
-------------------------------
-
-* :manual:`cmake-presets(7)` gained support for a new ``${hostSystemName}``
-  macro.

Help/release/dev/cmake-presets-optional-generator-and-binarydir.rst

-cmake-presets-optional-generator-and-binarydir
-----------------------------------------------
-
-* :manual:`cmake-presets(7)` now support omitting the ``generator`` and
-  ``binaryDir`` fields.

Help/release/dev/cmake-system-name-version.rst

-cmake-system-name-version
--------------------------
-
-* :variable:`CMAKE_HOST_SYSTEM_NAME`'s undocumented version-stripping behavior
-  has been moved earlier, before :command:`project` or
-  :command:`enable_language` is called.
-* :variable:`CMAKE_SYSTEM_NAME`'s undocumented version-stripping behavior has
-  been removed entirely. If it is set by a ``-D`` flag or by a
-  :manual:`toolchain file <cmake-toolchains(7)>`, it is left unaltered, even if
-  it still contains a version number.