CheckCSourceCompiles

Check once if C source code can be built.

check_c_source_compiles

check_c_source_compiles(<code> <resultVar>
                        [FAIL_REGEX <regex1> [<regex2>...]])

Check once that the source supplied in <code> can be built. The result is stored in the internal cache variable specified by <resultVar>, with boolean true for success and boolean false for failure.

If FAIL_REGEX is provided, then failure is determined by checking if anything in the compiler output matches any of the specified regular expressions.

Internally, try_compile() is used to compile the source. If CMAKE_TRY_COMPILE_TARGET_TYPE is set to EXECUTABLE (default), the source is compiled and linked as an executable program. If set to STATIC_LIBRARY, the source is compiled but not linked. In any case, all functions must be declared as usual.

See also check_source_compiles() for a more general command syntax.

See also check_source_runs() to run compiled source.

The compile and link commands can be influenced by setting any of the following variables prior to calling check_c_source_compiles():

CMAKE_REQUIRED_FLAGS

String of additional flags to pass to the compiler. The string must be space-delimited--a ;-list will not work. The contents of 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 ;-list 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 ;-list of header search paths to pass to the compiler. These will be the only header search paths used--the contents of the INCLUDE_DIRECTORIES directory property will be ignored.

CMAKE_REQUIRED_LINK_OPTIONS

Added in version 3.14.

A ;-list of options to add to the link command (see try_compile() for further details).

CMAKE_REQUIRED_LIBRARIES

A ;-list of libraries to add to the link command. These can be the name of system libraries or they can be Imported Targets (see try_compile() for further details).

CMAKE_REQUIRED_LINK_DIRECTORIES

Added in version 3.31.

A ;-list of libraries search paths to pass to the linker (see try_compile() for further details).

CMAKE_REQUIRED_QUIET

Added in version 3.1.

If this variable evaluates to a boolean true value, all status messages associated with the check will be suppressed.