# CMakeForceCompiler

Discouraged. Avoid using this module if possible. It will be deprecated by a future version of CMake once alternatives have been provided for all toolchain file use cases.

The macros provided by this module were once intended for use by cross-compiling toolchain files when CMake was not able to automatically detect the compiler identification. Since the introduction of this module, CMake’s compiler identification capabilities have improved and can now be taught to recognize any compiler. Furthermore, the suite of information CMake detects from a compiler is now too extensive to be provided by toolchain files using these macros.

The only known remaining use case for these macros is to write toolchain files for cross-compilers that cannot link binaries without special flags or custom linker scripts. These macros cause CMake to skip checks it normally performs as part of enabling a language and introspecting the toolchain. However, skipping these checks may limit some generation functionality.

Macro CMAKE_FORCE_C_COMPILER has the following signature:

    CMAKE_FORCE_C_COMPILER(<compiler> <compiler-id>)

It sets CMAKE_C_COMPILER to the given compiler and the cmake internal variable CMAKE_C_COMPILER_ID to the given compiler-id. It also bypasses the check for working compiler and basic compiler information tests.

Macro CMAKE_FORCE_CXX_COMPILER has the following signature:

    CMAKE_FORCE_CXX_COMPILER(<compiler> <compiler-id>)

It sets CMAKE_CXX_COMPILER to the given compiler and the cmake internal variable CMAKE_CXX_COMPILER_ID to the given compiler-id. It also bypasses the check for working compiler and basic compiler information tests.

Macro CMAKE_FORCE_Fortran_COMPILER has the following signature:

    CMAKE_FORCE_Fortran_COMPILER(<compiler> <compiler-id>)

It sets CMAKE_Fortran_COMPILER to the given compiler and the cmake internal variable CMAKE_Fortran_COMPILER_ID to the given compiler-id. It also bypasses the check for working compiler and basic compiler information tests.

So a simple toolchain file could look like this:

    include (CMakeForceCompiler)
    set(CMAKE_SYSTEM_NAME Generic)
    CMAKE_FORCE_C_COMPILER   (chc12 MetrowerksHicross)
    CMAKE_FORCE_CXX_COMPILER (chc12 MetrowerksHicross)