> Date: Wed, 10 May 2023 16:22:26 +0200 > From: Jakub Jelinek <ja...@redhat.com> > Cc: Gabriel Ravier <gabrav...@gmail.com>, jwakely....@gmail.com, > fwei...@redhat.com, gcc@gcc.gnu.org, ar...@aarsen.me > > > > Are you seriously saying that no accepts-invalid bug should ever be > > > fixed under any circumstances on the basis that some programmers might > > > rely on code exploiting that bug ?? > > > > Sorry, I'm afraid I don't understand the question. What are > > "accepts-invalid bugs"? > > They are bugs where compiler accepts something that isn't valid in > the selected language nor considered valid extension. > So, after the fix we reject something that has been accepted before.
If some program is plainly invalid, not just because the criteria of validity have shifted, then yes, such a program should be rejected. > What we are talking in this thread is also something not valid in C99 or > later, for the int-conversion stuff not even valid in C89, in the past > accepted just for K&R legacy reasons. Yes, and that's the crucial (for me) difference: what is currently considered invalid was valid in the past, and so there's a set of rules under which that kind of program can produce valid machine code.
