How to partially disabling cmake C/C++ custom compiler checking

Question

I am trying to do some crosscompilation using cmake. Some are easy with all the examples on Internet, I managed to crosscompile my library on Linux (x86 and ARM), Windows an

Answer 1

Without having your environment nor the error message it's not easy to tell the actual root cause but here are two of the common causes and respective fixes:

1. If you don't have a complete toolchain file created for your custom environment - so CMake can't link a simple test program - you can try the relatively new (version 3.6) global CMake variable named CMAKE_TRY_COMPILE_TARGET_TYPE.

   So just add the following:

   set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
   

   Then CMake would just try to build a static library.

2. To have only the most common GCC compiler variables set and have only some basic checks, try:

   SET(CMAKE_SYSTEM_NAME Generic)
   

   See CMake Cross Compiling: Setting up the system and toolchain:

   If your target is an embedded system without OS set CMAKE_SYSTEM_NAME to "Generic"

References

• CMake AMRCC + custom linker
• cmake cross-compile with specific linker doesn't pass arguments to armlink

Answer 2

Commandline:

    cmake ... \
    -DCMAKE_C_COMPILER_FORCED=TRUE \
    -DCMAKE_CXX_COMPILER_FORCED=TRUE

or

CMakeLists.txt

    ...
    set(CMAKE_C_COMPILER_FORCED TRUE)
    set(CMAKE_CXX_COMPILER_FORCED TRUE)
    ...

Works for me.