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+target_precompile_headers
+-------------------------
+
+Add a list of header files to precompile.
+
+Precompiling header files can speed up compilation by creating a partially
+processed version of some header files, and then using that version during
+compilations rather than repeatedly parsing the original headers.
+
+Main Form
+^^^^^^^^^
+
+.. code-block:: cmake
+
+  target_precompile_headers(<target>
+    <INTERFACE|PUBLIC|PRIVATE> [header1...]
+    [<INTERFACE|PUBLIC|PRIVATE> [header2...] ...])
+
+The command adds header files to the :prop_tgt:`PRECOMPILE_HEADERS` and/or
+:prop_tgt:`INTERFACE_PRECOMPILE_HEADERS` target properties of ``<target>``.
+The named ``<target>`` must have been created by a command such as
+:command:`add_executable` or :command:`add_library` and must not be an
+:ref:`ALIAS target <Alias Targets>`.
+
+The ``INTERFACE``, ``PUBLIC`` and ``PRIVATE`` keywords are required to
+specify the scope of the following arguments.  ``PRIVATE`` and ``PUBLIC``
+items will populate the :prop_tgt:`PRECOMPILE_HEADERS` property of
+``<target>``.  ``PUBLIC`` and ``INTERFACE`` items will populate the
+:prop_tgt:`INTERFACE_PRECOMPILE_HEADERS` property of ``<target>``
+(:ref:`IMPORTED targets <Imported Targets>` only support ``INTERFACE`` items).
+Repeated calls for the same ``<target>`` will append items in the order called.
+
+Projects should generally avoid using ``PUBLIC`` or ``INTERFACE`` for targets
+that will be :ref:`exported <install(EXPORT)>`, or they should at least use
+the ``$<BUILD_INTERFACE:...>`` generator expression to prevent precompile
+headers from appearing in an installed exported target.  Consumers of a target
+should typically be in control of what precompile headers they use, not have
+precompile headers forced on them by the targets being consumed (since
+precompile headers are not typically usage requirements).  A notable exception
+to this is where an :ref:`interface library <Interface Libraries>` is created
+to define a commonly used set of precompile headers in one place and then other
+targets link to that interface library privately.  In this case, the interface
+library exists specifically to propagate the precompile headers to its
+consumers and the consumer is effectively still in control, since it decides
+whether to link to the interface library or not.
+
+The list of header files is used to generate a header file named
+``cmake_pch.h|xx`` which is used to generate the precompiled header file
+(``.pch``, ``.gch``, ``.pchi``) artifact.  The ``cmake_pch.h|xx`` header
+file will be force included (``-include`` for GCC, ``/FI`` for MSVC) to
+all source files, so sources do not need to have ``#include "pch.h"``.
+
+Header file names specified with angle brackets (e.g. ``<unordered_map>``) or
+explicit double quotes (escaped for the :manual:`cmake-language(7)`,
+e.g. ``[["other_header.h"]]``) will be treated as is, and include directories
+must be available for the compiler to find them.  Other header file names
+(e.g. ``project_header.h``) are interpreted as being relative to the current
+source directory (e.g. :variable:`CMAKE_CURRENT_SOURCE_DIR`) and will be
+included by absolute path.
+
+Arguments to ``target_precompile_headers()`` may use "generator expressions"
+with the syntax ``$<...>``.
+See the :manual:`cmake-generator-expressions(7)` manual for available
+expressions.  See the :manual:`cmake-compile-features(7)` manual for
+information on compile features and a list of supported compilers.
+The ``$<COMPILE_LANGUAGE:...>`` generator expression is particularly
+useful for specifying a language-specific header to precompile for
+only one language (e.g. ``CXX`` and not ``C``).  For example:
+
+.. code-block:: cmake
+
+  target_precompile_headers(myTarget
+    PUBLIC
+      project_header.h
+      "$<$<COMPILE_LANGUAGE:CXX>:cxx_only.h>"
+    PRIVATE
+      [["other_header.h"]]
+      <unordered_map>
+  )
+
+When specifying angle brackets inside a :manual:`generator expression
+<cmake-generator-expressions(7)>`, be sure to encode the closing ``>``
+as ``$<ANGLE-R>``.  For example:
+
+.. code-block:: cmake
+
+  target_precompile_headers(mylib PRIVATE
+    "$<$<COMPILE_LANGUAGE:C>:<stddef.h$<ANGLE-R>>"
+    "$<$<COMPILE_LANGUAGE:CXX>:<cstddef$<ANGLE-R>>"
+  )
+
+
+Reusing Precompile Headers
+^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The command also supports a second signature which can be used to specify that
+one target re-uses a precompiled header file artefact from another target
+instead of generating its own:
+
+.. code-block:: cmake
+
+  target_precompile_headers(<target> REUSE_FROM <other_target>)
+
+This form sets the :prop_tgt:`PRECOMPILE_HEADERS_REUSE_FROM` property to
+``<other_target>`` and adds a dependency such that ``<target>`` will depend
+on ``<other_target>``.  CMake will halt with an error if the
+:prop_tgt:`PRECOMPILE_HEADERS` property of ``<target>`` is already set when
+the ``REUSE_FROM`` form is used.
+
+.. note::
+
+  The ``REUSE_FROM`` form requires the same set of compiler options,
+  compiler flags and compiler definitions for both ``<target>`` and
+  ``<other_target>``.  Some compilers (e.g. GCC) may issue a warning if the
+  precompiled header file cannot be used (``-Winvalid-pch``).
+
+See Also
+^^^^^^^^
+
+To disable precompile headers for specific targets, see the
+:prop_tgt:`DISABLE_PRECOMPILE_HEADERS` target property.
+
+To prevent precompile headers from being used when compiling a specific
+source file, see the :prop_sf:`SKIP_PRECOMPILE_HEADERS` source file property.