Hello, I built a new gcc front end I would like to use the -fopenmp options when compiling my source file I could use the C front end options like -S -fdump-tree-all -O*, .... but when I use -fopenmp I get this error: uml1: warning: command line option â-fopenmpâ is valid for C/C++/Fortran/ObjC/ObjC++ but not for [enabled by default] should I modify my lang-specs.h ? If yes what kind of modification ? here is its content: {".uml", "@uml", 0, 1, 0}, {"@uml", "uml1 %i %(invoke_as)", 0, 1, 0}, {"@uml", "uml1 %i %(cc1_options) %{!fsyntax-only:%(invoke_as)}", 0, 1, 0}, thank you very much Asma