https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68095
--- Comment #6 from David <gccbugzilla at limegreensocks dot com> --- Created attachment 37621 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=37621&action=edit Patch for missing clobber validations I have created a patch (attached) that does the check I am describing. And while I was at it, I added a few other validations for clobber conditions. The patch includes testcases, but in short, these lines (which currently produce no messages) would all give errors: __asm__ volatile("":::"eax","eax"); __asm__ volatile("":::"memory", "memory"); __asm__ volatile("":::"cc", "cc"); __asm__ volatile("":"=@ccc"(c)::"cc");