Co pro gcc toto:
-fdiagnostics-color=WHEN
-fno-diagnostics-color
Use color in diagnostics. WHEN is never, always, or auto. The default depends on how the compiler has been configured, it can be any of the above WHEN options or also never if GCC_COLORS environment variable isn't
present in the environment, and auto otherwise. auto makes GCC use color only when the standard error is a terminal, and when not executing in an emacs shell. The forms -fdiagnostics-color and -fno-diagnostics-color
are aliases for -fdiagnostics-color=always and -fdiagnostics-color=never, respectively.