CMake/Modules/CheckCSourceCompiles.cmake
Brad King cabb6cd00e Document Check(C|CXX)SourceCompiles behavior more clearly (#11688)
Explicitly state up front that the macros try to link an executable and
that the source provided must define 'main'.
2011-01-14 07:36:59 -05:00

91 lines
3.6 KiB
CMake

# - Check if given C source compiles and links into an executable
# CHECK_C_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
# <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
#=============================================================================
# Copyright 2005-2009 Kitware, Inc.
#
# Distributed under the OSI-approved BSD License (the "License");
# see accompanying file Copyright.txt for details.
#
# This software is distributed WITHOUT ANY WARRANTY; without even the
# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the License for more information.
#=============================================================================
# (To distribute this file outside of CMake, substitute the full
# License text for the above reference.)
MACRO(CHECK_C_SOURCE_COMPILES SOURCE VAR)
IF("${VAR}" MATCHES "^${VAR}$")
SET(_FAIL_REGEX)
SET(_key)
FOREACH(arg ${ARGN})
IF("${arg}" MATCHES "^(FAIL_REGEX)$")
SET(_key "${arg}")
ELSEIF(_key)
LIST(APPEND _${_key} "${arg}")
ELSE()
MESSAGE(FATAL_ERROR "Unknown argument:\n ${arg}\n")
ENDIF()
ENDFOREACH()
SET(MACRO_CHECK_FUNCTION_DEFINITIONS
"-D${VAR} ${CMAKE_REQUIRED_FLAGS}")
IF(CMAKE_REQUIRED_LIBRARIES)
SET(CHECK_C_SOURCE_COMPILES_ADD_LIBRARIES
"-DLINK_LIBRARIES:STRING=${CMAKE_REQUIRED_LIBRARIES}")
ELSE(CMAKE_REQUIRED_LIBRARIES)
SET(CHECK_C_SOURCE_COMPILES_ADD_LIBRARIES)
ENDIF(CMAKE_REQUIRED_LIBRARIES)
IF(CMAKE_REQUIRED_INCLUDES)
SET(CHECK_C_SOURCE_COMPILES_ADD_INCLUDES
"-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
ELSE(CMAKE_REQUIRED_INCLUDES)
SET(CHECK_C_SOURCE_COMPILES_ADD_INCLUDES)
ENDIF(CMAKE_REQUIRED_INCLUDES)
FILE(WRITE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.c"
"${SOURCE}\n")
MESSAGE(STATUS "Performing Test ${VAR}")
TRY_COMPILE(${VAR}
${CMAKE_BINARY_DIR}
${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.c
COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_FUNCTION_DEFINITIONS}
"${CHECK_C_SOURCE_COMPILES_ADD_LIBRARIES}"
"${CHECK_C_SOURCE_COMPILES_ADD_INCLUDES}"
OUTPUT_VARIABLE OUTPUT)
FOREACH(_regex ${_FAIL_REGEX})
IF("${OUTPUT}" MATCHES "${_regex}")
SET(${VAR} 0)
ENDIF()
ENDFOREACH()
IF(${VAR})
SET(${VAR} 1 CACHE INTERNAL "Test ${VAR}")
MESSAGE(STATUS "Performing Test ${VAR} - Success")
FILE(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
"Performing C SOURCE FILE Test ${VAR} succeded with the following output:\n"
"${OUTPUT}\n"
"Source file was:\n${SOURCE}\n")
ELSE(${VAR})
MESSAGE(STATUS "Performing Test ${VAR} - Failed")
SET(${VAR} "" CACHE INTERNAL "Test ${VAR}")
FILE(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
"Performing C SOURCE FILE Test ${VAR} failed with the following output:\n"
"${OUTPUT}\n"
"Source file was:\n${SOURCE}\n")
ENDIF(${VAR})
ENDIF("${VAR}" MATCHES "^${VAR}$")
ENDMACRO(CHECK_C_SOURCE_COMPILES)