http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50191
Bug #: 50191 Summary: Strange debug insn produced for TOC compiling 416.gamess with profile-generate Classification: Unclassified Product: gcc Version: 4.7.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: rtl-optimization AssignedTo: unassig...@gcc.gnu.org ReportedBy: wschm...@gcc.gnu.org CC: berg...@gcc.gnu.org, meiss...@gcc.gnu.org, pthau...@gcc.gnu.org Host: powerpc64-linux Target: powerpc64-linux Build: powerpc64-linux Created attachment 25107 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25107 Failing source code I opened a bug against binutils (http://sourceware.org/bugzilla/show_bug.cgi?id=13131) for the linkage error described there. However, Alan Modra determined the linker was confused by a strange debug_insn reference into the TOC, produced by gcc: (debug_insn 8390 8396 8395 5 (var_location:DI D#142 (mem/u/c:DI (lo_sum:DI (reg/f:DI 2011) (const:DI (unspec:DI [ (symbol_ref/u:DI ("*.LC7") [flags 0x2]) ] UNSPEC_TOCREL))) [23 S8 A8])) -1 (nil)) The debug_insn appears to be modified during combine; prior to that it contains the more innocuous: (debug_insn 8390 8396 8395 5 (var_location:DI D#142 (reg/f:DI 1243 [ ivtmp.961 ])) -1 (nil)) This occurs when compiling chgpen.fppized.f (attached) with the following minimal set of options: > /home/wschmidt/gcc/install/gcc-mainline-base/libexec/gcc/powerpc64-linux/4.7.0/f951 > chgpen.fppized.f -g -O3 -fprofile-generate -ffast-math -funroll-loops -o > chgpen.fppized.s