https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61904
--- Comment #9 from Andrew Pinski <pinskia at gcc dot gnu.org> --- (In reply to Linus Torvalds from comment #8) > Oh, and this is marked as a duplicate of 61801, but that one is marked to be > in gcc-4.8.3 > > The particular problem we see in kernel code generation seems to *not* > happen in 4.8.3 (current fedora 20), and happens with Debian 4.9.0. Different optimization happen before the scheduler between 4.8.3 and 4.9.0 which causes the difference. > > So now I worry about > > (a) whether the duplicate bug is really true It is as the true issue was fixed there. > > (b) or perhaps 4.8.3 really does have the same problem and we might get > bitten there too, and it just happens to trigger on 4.9.0 for some otherwise > unrelated reason. Correct. > > I'd like to have some way to tell known-bad compilers, so that we know to > avoid them.. The bad compiler versions are 4.5.0 (when debug_insn came in) to 4.8.3 and 4.9.0 and 4.9.1.
