https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115284
--- Comment #11 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot Uni-Bielefeld.DE> --- > --- Comment #10 from Hans-Peter Nilsson <hp at gcc dot gnu.org> --- > (In reply to r...@cebitec.uni-bielefeld.de from comment #9) >> > --- Comment #8 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot >> > Uni-Bielefeld.DE> --- >> >> --- Comment #6 from Hans-Peter Nilsson <hp at gcc dot gnu.org> --- >> [...] >> >> versions.) BTW, it'd be nice to know it it reproduces for sparc-linux >> >> as well. >> > >> > I happen to have a Linux/sparc64 LDom around: I'll give it a whirl. >> >> The failure is even earlier here: in a sparc64-unknown-linux-gnu >> bootstrap, building a libstdc++ .gch file in stage 2 breaks: > > Great, thanks! That means that tricking my pc into believing it's a sparc by > means of using the binfmt machinery that Jeff mentioned in the thread where I > mentioned the revert on gcc-patches, would work. (I don't have the details > and > don't remember if I'd actually tried it, certainly not recently; I just know > about the concept.) I can't help but wonder if this wouldn't be a total waste of your time: considering what the qemu wiki docments for SPARC support https://wiki.qemu.org/Documentation/Platforms/SPARC seems not too encouraging for 64-bit systems. When I think about what it took myself to get recent macOS working on qemu-kvm (although the procedure is resonably well documented, with firmware and all available), I'd consider such an attempt a positive nightmare. When all it takes for you to either get your ssh client working to access a ready-made and not too slow SPARC system (or in the worst case, build OpenSSH from source), I know which route I'd take ;-) > What's not so great is that the described reproducer is a bootstrap, so the > debug situation is unpleasant. The first step I'd do, would be to just do a > cross-build (or native --disable-bootstrap) and just run the testsuite > before/after the patch-set (or just 933ab59c59bdc1) and see if the problem > manifests there. > > It's also not great (from the view of gcc targeting architectures with > delay-slots) that this isn't at the top of my queue anymore, since the > immediate situation was resolved; as mentioned I committed the revert. I'll > get to it eventually, but if someone is intrigued enough by the prospect of a > 0.36%-ish performance improvement (see commit log for the culprit commit) to > do > such a --disable-bootstrap regtest, that'd help. :) I've tried that now on both * sparc-sun-solaris2.11 (c and c++ only): no additional testsuite failures are apparent there, which is not too astonishing given that the bootstrap failure occurs in stage 3, suggesting a mis-compiled stage 2 cc1plus, and * sparc64-unknown-linux-gnu (again, c and c++ only): there are testsuite failures all over the place, but I'd have to perform another bootstrap with your patches removed to make an exact comparison.
