mex compilation error : collect2.exe: error: ld returned 5 exit status

Hi,

I'm trying to compile cpp code to create mexw64 files directly usable in Matlab.

Using "mex" function I get this error message:

I do not ask people to give me THE solution to this trouble, but:

• Does anyone now if a document explaining all ld function exit status meanings exist? If yes, where can I find it?
• Does anyone can give me any idea of how I can find where the trouble come from? A list of checks, step by step, to ensure I finally find the solution...

I'm using MinGW34 on Matlab R2018b.

Thanks.