https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97989
--- Comment #23 from Stas Sergeev <stsp at users dot sourceforge.net> --- (In reply to Jakub Jelinek from comment #22) > -S -fpreprocessed test.i will not work It doesn't seem to support -fpreprocessed though. Thanks for explanations and sorry about naively attributing that effect to -P.