Thank you for the quick reply jens.
Actually, I'm running my program as a makefile. I defined it as a makefile (in toolchain) for a new (custom) compiler in the "Compiler and Debugger" settings.
Then, in "build options", I just use "$make". And yes, it's running and it has output, but not showing in the "Build log" tab.
Btw, now I set it as a pre-build step (and took out the $make), and it's working perfect.