https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96304
--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> --- (In reply to Martin Liška from comment #3) > > But, are we violating aliasing rules here? What am I missing? > > Likely you are, but I must admit it's sometimes quite difficult to find that. > From quickly looking at the function, you may violate it here: > > MemJournal *p = (MemJournal*)pJfd; > > maybe > > MemJournal *p = (MemJournal*)(char*)pJfd; > > can solve it. > Unfortunately I can't reproduce it on my x86_64-linux box. An intermediate cast does never solve any strict-aliasing issue.