CheckSourceCompiles¶
Added in version 3.19.
Check once if source code can be built for a given language.
- check_source_compiles¶
check_source_compiles(<lang> <code> <resultVar> [FAIL_REGEX <regex1> [<regex2>...]] [SRC_EXT <extension>])
Check once that the source supplied in
<code>can be built for code language<lang>. The result is stored in the internal cache variable specified by<resultVar>, with booleantruefor success and booleanfalsefor failure.If
FAIL_REGEXis provided, then failure is determined by checking if anything in the compiler output matches any of the specified regular expressions.By default, the test source file will be given a file extension that matches the requested language. The
SRC_EXToption can be used to override this with.<extension>instead.The C example checks if the compiler supports the
noreturnattribute:set(CMAKE_TRY_COMPILE_TARGET_TYPE "STATIC_LIBRARY") check_source_compiles(C "#if !__has_c_attribute(noreturn) #error \"No noreturn attribute\" #endif" HAVE_NORETURN)
The Fortran example checks if the compiler supports the
pureprocedure attribute:set(CMAKE_TRY_COMPILE_TARGET_TYPE "STATIC_LIBRARY") check_source_compiles(Fortran "pure subroutine foo() end subroutine" HAVE_PURE)
Internally,
try_compile()is used to compile the source. IfCMAKE_TRY_COMPILE_TARGET_TYPEis set toEXECUTABLE(default), the source is compiled and linked as an executable program. If set toSTATIC_LIBRARY, the source is compiled but not linked. In any case, all functions must be declared as usual.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_source_compiles():
CMAKE_REQUIRED_FLAGSString of additional flags to pass to the compiler. The string must be space-delimited--a ;-list will not work. The contents of
CMAKE_<LANG>_FLAGSand its associated configuration-specific variable are automatically added to the compiler command before the contents ofCMAKE_REQUIRED_FLAGS.
CMAKE_REQUIRED_DEFINITIONSA ;-list of compiler definitions of the form
-DFOOor-DFOO=bar. A definition for the name specified by<resultVar>will also be added automatically.
CMAKE_REQUIRED_INCLUDESA ;-list of header search paths to pass to the compiler. These will be the only header search paths used--the contents of the
INCLUDE_DIRECTORIESdirectory property will be ignored.
CMAKE_REQUIRED_LINK_OPTIONSAdded in version 3.14.
A ;-list of options to add to the link command (see
try_compile()for further details).
CMAKE_REQUIRED_LIBRARIESA ;-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_DIRECTORIESAdded in version 3.31.
A ;-list of libraries search paths to pass to the linker (see
try_compile()for further details).
CMAKE_REQUIRED_QUIETAdded in version 3.1.
If this variable evaluates to a boolean true value, all status messages associated with the check will be suppressed.