CMake/Modules/CheckCXXSourceRuns.cmake
2018-12-01 17:56:23 +01:00

141 lines
5.6 KiB
CMake

# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.
#[=======================================================================[.rst:
CheckCXXSourceRuns
------------------
Check if given C++ source compiles and links into an executable and can
subsequently be run.
.. command:: check_cxx_source_runs
.. code-block:: cmake
check_cxx_source_runs(<code> <resultVar>)
Check that the source supplied in ``<code>`` can be compiled as a C++ source
file, linked as an executable and then run. The ``<code>`` must contain at
least a ``main()`` function. If the ``<code>`` could be built and run
successfully, the internal cache variable specified by ``<resultVar>`` will
be set to 1, otherwise it will be set to an value that evaluates to boolean
false (e.g. an empty string or an error message).
The underlying check is performed by the :command:`try_run` command. The
compile and link commands can be influenced by setting any of the following
variables prior to calling ``check_cxx_source_runs()``:
``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_run()``, i.e. the contents of the :prop_dir:`INCLUDE_DIRECTORIES`
directory property will be ignored.
``CMAKE_REQUIRED_LINK_OPTIONS``
A :ref:`;-list <CMake Language Lists>` of options to add to the link
command (see :command:`try_run` for further details).
``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_run` 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.
#]=======================================================================]
include_guard(GLOBAL)
macro(CHECK_CXX_SOURCE_RUNS SOURCE VAR)
if(NOT DEFINED "${VAR}")
set(MACRO_CHECK_FUNCTION_DEFINITIONS
"-D${VAR} ${CMAKE_REQUIRED_FLAGS}")
if(CMAKE_REQUIRED_LINK_OPTIONS)
set(CHECK_CXX_SOURCE_COMPILES_ADD_LINK_OPTIONS
LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
else()
set(CHECK_CXX_SOURCE_COMPILES_ADD_LINK_OPTIONS)
endif()
if(CMAKE_REQUIRED_LIBRARIES)
set(CHECK_CXX_SOURCE_COMPILES_ADD_LIBRARIES
LINK_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
else()
set(CHECK_CXX_SOURCE_COMPILES_ADD_LIBRARIES)
endif()
if(CMAKE_REQUIRED_INCLUDES)
set(CHECK_CXX_SOURCE_COMPILES_ADD_INCLUDES
"-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
else()
set(CHECK_CXX_SOURCE_COMPILES_ADD_INCLUDES)
endif()
file(WRITE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.cxx"
"${SOURCE}\n")
if(NOT CMAKE_REQUIRED_QUIET)
message(STATUS "Performing Test ${VAR}")
endif()
try_run(${VAR}_EXITCODE ${VAR}_COMPILED
${CMAKE_BINARY_DIR}
${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.cxx
COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
${CHECK_CXX_SOURCE_COMPILES_ADD_LINK_OPTIONS}
${CHECK_CXX_SOURCE_COMPILES_ADD_LIBRARIES}
CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_FUNCTION_DEFINITIONS}
-DCMAKE_SKIP_RPATH:BOOL=${CMAKE_SKIP_RPATH}
"${CHECK_CXX_SOURCE_COMPILES_ADD_INCLUDES}"
COMPILE_OUTPUT_VARIABLE OUTPUT)
# if it did not compile make the return value fail code of 1
if(NOT ${VAR}_COMPILED)
set(${VAR}_EXITCODE 1)
endif()
# if the return value was 0 then it worked
if("${${VAR}_EXITCODE}" EQUAL 0)
set(${VAR} 1 CACHE INTERNAL "Test ${VAR}")
if(NOT CMAKE_REQUIRED_QUIET)
message(STATUS "Performing Test ${VAR} - Success")
endif()
file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
"Performing C++ SOURCE FILE Test ${VAR} succeeded with the following output:\n"
"${OUTPUT}\n"
"Return value: ${${VAR}}\n"
"Source file was:\n${SOURCE}\n")
else()
if(CMAKE_CROSSCOMPILING AND "${${VAR}_EXITCODE}" MATCHES "FAILED_TO_RUN")
set(${VAR} "${${VAR}_EXITCODE}")
else()
set(${VAR} "" CACHE INTERNAL "Test ${VAR}")
endif()
if(NOT CMAKE_REQUIRED_QUIET)
message(STATUS "Performing Test ${VAR} - Failed")
endif()
file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
"Performing C++ SOURCE FILE Test ${VAR} failed with the following output:\n"
"${OUTPUT}\n"
"Return value: ${${VAR}_EXITCODE}\n"
"Source file was:\n${SOURCE}\n")
endif()
endif()
endmacro()