rlm@0: # - Check if the C source code provided in the SOURCE argument compiles.
rlm@0: # CHECK_C_SOURCE_COMPILES(SOURCE VAR)
rlm@0: #
rlm@0: #  FLAG   - compiler flag to check
rlm@0: #  VAR    - variable to store whether the source code compiled
rlm@0: #
rlm@0: # The following variables may be set before calling this macro to
rlm@0: # modify the way the check is run:
rlm@0: #
rlm@0: #  CMAKE_REQUIRED_FLAGS = string of compile command line flags
rlm@0: #  CMAKE_REQUIRED_DEFINITIONS = list of macros to define (-DFOO=bar)
rlm@0: #  CMAKE_REQUIRED_INCLUDES = list of include directories
rlm@0: #  CMAKE_REQUIRED_LIBRARIES = list of libraries to link
rlm@0: 
rlm@0: MACRO(CHECK_C_COMPILER_FLAG FLAG VAR)
rlm@0:   IF("${VAR}" MATCHES "^${VAR}$")
rlm@0:     SET(MACRO_CHECK_FUNCTION_DEFINITIONS
rlm@0:       "${FLAG} ${CMAKE_REQUIRED_FLAGS}")
rlm@0:     IF(CMAKE_REQUIRED_LIBRARIES)
rlm@0:       SET(CHECK_C_COMPILER_FLAG_ADD_LIBRARIES
rlm@0:         "-DLINK_LIBRARIES:STRING=${CMAKE_REQUIRED_LIBRARIES}")
rlm@0:     ELSE(CMAKE_REQUIRED_LIBRARIES)
rlm@0:       SET(CHECK_C_COMPILER_FLAG_ADD_LIBRARIES)
rlm@0:     ENDIF(CMAKE_REQUIRED_LIBRARIES)
rlm@0:     IF(CMAKE_REQUIRED_INCLUDES)
rlm@0:       SET(CHECK_C_COMPILER_FLAG_ADD_INCLUDES
rlm@0:         "-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
rlm@0:     ELSE(CMAKE_REQUIRED_INCLUDES)
rlm@0:       SET(CHECK_C_COMPILER_FLAG_ADD_INCLUDES)
rlm@0:     ENDIF(CMAKE_REQUIRED_INCLUDES)
rlm@0:     FILE(WRITE "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.c"
rlm@0:       "int main() {return 0;}\n")
rlm@0: 
rlm@0:     MESSAGE(STATUS "Checking if C compiler supports ${FLAG}")
rlm@0:     TRY_COMPILE(${VAR}
rlm@0:       ${CMAKE_BINARY_DIR}
rlm@0:       ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/src.c
rlm@0:       COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
rlm@0:       CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_FUNCTION_DEFINITIONS}
rlm@0:       "${CHECK_C_COMPILER_FLAG_ADD_LIBRARIES}"
rlm@0:       "${CHECK_C_COMPILER_FLAG_ADD_INCLUDES}"
rlm@0:       OUTPUT_VARIABLE OUTPUT)
rlm@0:     IF(${VAR})
rlm@0:       SET(${VAR} 1 CACHE INTERNAL "Test ${VAR}")
rlm@0:       MESSAGE(STATUS "Checking if C compiler supports ${FLAG} - Success")
rlm@0:       FILE(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
rlm@0:         "Performing C SOURCE FILE Test ${VAR} succeded with the following output:\n"
rlm@0:         "${OUTPUT}\n"
rlm@0:         "Source file was:\n${SOURCE}\n")
rlm@0:     ELSE(${VAR})
rlm@0:       MESSAGE(STATUS "Checking if C compiler supports ${FLAG} - Failed")
rlm@0:       SET(${VAR} "" CACHE INTERNAL "Test ${VAR}")
rlm@0:       FILE(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
rlm@0:         "Performing C SOURCE FILE Test ${VAR} failed with the following output:\n"
rlm@0:         "${OUTPUT}\n"
rlm@0:         "Source file was:\n${SOURCE}\n")
rlm@0:     ENDIF(${VAR})
rlm@0:   ENDIF("${VAR}" MATCHES "^${VAR}$")
rlm@0: ENDMACRO(CHECK_C_COMPILER_FLAG)