https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113050
--- Comment #3 from Florian Weimer <fw at gcc dot gnu.org> --- (In reply to Florian Weimer from comment #1) > The warning should be -Wdiscared-qualifiers, which is not an error for C. > > What confused me is that the volatile qualifier is already accepted for the > first argument. I believe it's valid for the second argument. Sorry, I wanted to say: “I believe [the warning is] valid for the second argument.”