FindSWIG

Finds the installed Simplified Wrapper and Interface Generator (SWIG) executable and determines its version:

find_package(SWIG [<version>] [COMPONENTS <langs>...] [...])

Added in version 3.19: Support for specifying version range when calling the find_package() command. When a version is requested, it can be specified as a single value as before, and now also a version range can be used. For a detailed description of version range usage and capabilities, refer to the find_package() command.

Components

Added in version 3.18.

This module supports optional components to specify target languages.

If a COMPONENTS or OPTIONAL_COMPONENTS argument is given to the find_package() command, it will also determine supported target languages.

find_package(SWIG [COMPONENTS <langs>...] [OPTIONAL_COMPONENTS <langs>...])

Any COMPONENTS given to find_package() should be the names of supported target languages as provided to the LANGUAGE argument of swig_add_library(), such as python or perl5. Language names must be lowercase.

Result Variables

This module defines the following variables:

SWIG_FOUND

Boolean indicating whether (the requested version of) SWIG and any required components were found on the system.

SWIG_VERSION

SWIG executable version (result of swig -version).

SWIG_<lang>_FOUND

If COMPONENTS or OPTIONAL_COMPONENTS are requested, each available target language <lang> (lowercase) will be set to TRUE.

SWIG_DIR

Path to the installed SWIG Lib directory (result of swig -swiglib).

Cache Variables

The following cache variables may also be set:

SWIG_EXECUTABLE

The path to the SWIG executable.

This executable is used to retrieve all information for this module. It can be also manually set to change the version to be found from the command line.

Examples

Example usage requiring SWIG 4.0 or higher and Python language support, with optional Fortran support:

find_package(SWIG 4.0 COMPONENTS python OPTIONAL_COMPONENTS fortran)
if(SWIG_FOUND)
  message("SWIG found: ${SWIG_EXECUTABLE}")
  if(NOT SWIG_fortran_FOUND)
    message(WARNING "SWIG Fortran bindings cannot be generated")
  endif()
endif()

This module is commonly used in conjunction with the UseSWIG module:

find_package(SWIG COMPONENTS python)
if(SWIG_FOUND)
  include(UseSWIG)

  swig_add_library(mymod LANGUAGE python SOURCES mymod.i)
endif()

See Also

• The UseSWIG module to use SWIG in CMake.