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-rw-r--r--Modules/CheckCXXSourceCompiles.cmake83
1 files changed, 58 insertions, 25 deletions
diff --git a/Modules/CheckCXXSourceCompiles.cmake b/Modules/CheckCXXSourceCompiles.cmake
index e54d09e..4634a7b 100644
--- a/Modules/CheckCXXSourceCompiles.cmake
+++ b/Modules/CheckCXXSourceCompiles.cmake
@@ -1,31 +1,64 @@
# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.
-#.rst:
-# CheckCXXSourceCompiles
-# ----------------------
-#
-# Check if given C++ source compiles and links into an executable
-#
-# CHECK_CXX_SOURCE_COMPILES(<code> <var> [FAIL_REGEX <fail-regex>])
-#
-# ::
-#
-# <code> - source code to try to compile, must define 'main'
-# <var> - variable to store whether the source code compiled
-# Will be created as an internal cache variable.
-# <fail-regex> - fail if test output matches this regex
-#
-# The following variables may be set before calling this macro to modify
-# the way the check is run:
-#
-# ::
-#
-# CMAKE_REQUIRED_FLAGS = string of compile command line flags
-# CMAKE_REQUIRED_DEFINITIONS = list of macros to define (-DFOO=bar)
-# CMAKE_REQUIRED_INCLUDES = list of include directories
-# CMAKE_REQUIRED_LIBRARIES = list of libraries to link
-# CMAKE_REQUIRED_QUIET = execute quietly without messages
+#[=======================================================================[.rst:
+CheckCXXSourceCompiles
+----------------------
+
+Check if given C++ source compiles and links into an executable.
+
+.. command:: check_cxx_source_compiles
+
+ ::
+
+ check_cxx_source_compiles(code resultVar [FAIL_REGEX regex1 [regex2...]])
+
+ Check that the source supplied in ``code`` can be compiled as a C++ source
+ file and linked as an executable (so it must contain at least a ``main()``
+ function). The result will be stored in the internal cache variable specified
+ by ``resultVar``, with a boolean true value for success and boolean false for
+ failure. If ``FAIL_REGEX`` is provided, then failure is determined by
+ checking if anything in the output matches any of the specified regular
+ expressions.
+
+ The underlying check is performed by the :command:`try_compile` command. The
+ compile and link commands can be influenced by setting any of the following
+ variables prior to calling ``check_cxx_source_compiles()``:
+
+ ``CMAKE_REQUIRED_FLAGS``
+ Additional flags to pass to the compiler. Note that the contents of
+ :variable:`CMAKE_CXX_FLAGS <CMAKE_<LANG>_FLAGS>` and its associated
+ configuration-specific variable are automatically added to the compiler
+ command before the contents of ``CMAKE_REQUIRED_FLAGS``.
+
+ ``CMAKE_REQUIRED_DEFINITIONS``
+ A :ref:`;-list <CMake Language Lists>` of compiler definitions of the form
+ ``-DFOO`` or ``-DFOO=bar``. A definition for the name specified by
+ ``resultVar`` will also be added automatically.
+
+ ``CMAKE_REQUIRED_INCLUDES``
+ A :ref:`;-list <CMake Language Lists>` of header search paths to pass to
+ the compiler. These will be the only header search paths used by
+ ``try_compile()``, i.e. the contents of the :prop_dir:`INCLUDE_DIRECTORIES`
+ directory property will be ignored.
+
+ ``CMAKE_REQUIRED_LIBRARIES``
+ A :ref:`;-list <CMake Language Lists>` of libraries to add to the link
+ command. These can be the name of system libraries or they can be
+ :ref:`Imported Targets <Imported Targets>` (see :command:`try_compile` for
+ further details).
+
+ ``CMAKE_REQUIRED_QUIET``
+ If this variable evaluates to a boolean true value, all status messages
+ associated with the check will be suppressed.
+
+ The check is only performed once, with the result cached in the variable
+ named by ``resultVar``. Every subsequent CMake run will re-use this cached
+ value rather than performing the check again, even if the ``code`` changes.
+ In order to force the check to be re-evaluated, the variable named by
+ ``resultVar`` must be manually removed from the cache.
+
+#]=======================================================================]
macro(CHECK_CXX_SOURCE_COMPILES SOURCE VAR)
if(NOT DEFINED "${VAR}")