https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113341
Xi Ruoyao <xry111 at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |xry111 at gcc dot gnu.org --- Comment #12 from Xi Ruoyao <xry111 at gcc dot gnu.org> --- (In reply to John Paul Adrian Glaubitz from comment #11) > (In reply to John Paul Adrian Glaubitz from comment #10) > > (In reply to Kewen Lin from comment #9) > > > Since it's a breakage during stage2, it's concluded that some built stage1 > > > stuffs behave unexpectedly. You probably can try to run regression > > > testing > > > just with stage1 compiler to see if there is any regression exposed. > > > > > > If without any luck, then you probably have to isolate into one or several > > > object files, since you have "objects" for "good" and "bad" stage1 > > > compiler, > > > you can be able to isolate some in between further. Once you get some > > > isolated, you can probably get some hints it's a bug in LLVM source or > > > gcc. > > > > Thanks. This sounds like a good idea. I will try to identify the object > > files that differ. > > First result of the comparison is that Clang and GCC are building with > different flags: > > Clang-only flags: -Werror=unguarded-availability-new > -Wc++98-compat-extra-semi -Wcovered-switch-default -Wnon-virtual-dtor > -Wstring-conversion -Wmisleading-indentation > > GCC-only flags: -fno-lifetime-dse -Wno-missing-field-initializers > -Wno-maybe-uninitialized -Wno-nonnull -Wno-class-memaccess > -Wno-redundant-move -Wno-pessimizing-move -Wno-comment > -Wno-misleading-indentation > > I'll upload the build results later to my cloud space if anyone wants to > help debug as the diff between the two build folders is rather big. -Wxxx shouldn't have an effect on code generation. -fno-lifetime-dse is quite intentional, see PR106943.