Fixed bug for GCC version 14.1+

[emsmpokos]

Hello everyone,

It is my first time trying to change something on a github repository that I do now own, so I am not sure if forking it and then making a pull request is the way to go so sorry about that part.

So, in Source Installation, it says that you need to have "gcc >=4.4.7" but there is an issue with it now. In the newest version which is 14.1+ , the GCC compiler no longer tolerates some errors and thus it terminates the installation when using "make" (https://gcc.gnu.org/gcc-14/porting_to.html#c). The only way to bypass it is to add the following line on the CMakeList.txt :

Add the -fpermissive flag

set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fpermissive")

After doing that, I managed to finish the installation and check that the executables were running fine. If there is something else that I need to mention or do please tell me!

I have attached an image of the error that I was getting.

[jhunkeler]

Hi @emsmpokos, thank you for reporting this and taking the time to put in a PR to correct the issue. I consider the compiler's error to be a bug in our code, so we'll have to look into fixing those on our end.

I think that -fpermissive has the potential to mask problems we may want to address in the future. The following tests if the compiler throws an error on incompatible pointer types, and if so disables -Wincompatible-pointer-types via -Wno-incompatible-pointer-types.

if(NOT DEFINED COMPILER_ALLOWS_INCOMPAT_PTR)
        try_compile(COMPILER_ALLOWS_INCOMPAT_PTR
                SOURCE_FROM_CONTENT
                        incompatible_pointer_type.c
                        "char data[100]; char *datap = &data;"
        )

        if(NOT COMPILER_ALLOWS_INCOMPAT_PTR)
                message(STATUS "Incompatible pointer types are errors - yes")
                if(CMAKE_C_COMPILER_ID STREQUAL "Clang" OR CMAKE_C_COMPILER_ID STREQUAL "GNU")
                        set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-incompatible-pointer-types")
                endif()
        else()
                message(STATUS "Incompatible pointer types are errors - no")
        endif()
endif()

The outer if(NOT DEFINED ...)/endif() block prevents this check from executing more than once.