https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69819
kugan at gcc dot gnu.org changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |kugan at gcc dot gnu.org --- Comment #1 from kugan at gcc dot gnu.org --- It looks like a C front-end bug.It should be able to see that "foo" is already defined and flag an error. C++ front-end does just that.