https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89808
Jakub Jelinek <jakub at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jakub at gcc dot gnu.org --- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> --- You haven't explained why do you need to use #pragma once in the main cpp source file, are you sometimes including it as a header and other times compiling it as the TU itself? Not to mention that it is best not to use #pragma once at all anywhere.