------- Comment #9 from law at redhat dot com 2006-03-23 09:48 ------- Subject: Re: [4.2 Regression] ICE at gcc/tree-gimple.c:269
On Thu, 2006-03-23 at 00:09 +0000, pinskia at gcc dot gnu dot org wrote: > > ------- Comment #5 from pinskia at gcc dot gnu dot org 2006-03-23 00:09 > ------- > I see a similar failure in galgel on Diego's testers: > /home/cygnus/dnovillo/perf/sbox/gcc/local.i686/inst.tobiano/bin/gfortran -c -o > bifgel.o -ffixed-form -ffloat-store -O2 -march=pentium4 > -mtune=generic bifgel.f90 > Error from make 'specmake build 2> make.err | tee make.out': > bifgel.f90: In function 'bifgel': > bifgel.f90:1: internal compiler error: Segmentation fault > Please submit a full bug report, > with preprocessed source if appropriate. > See <URL:http://gcc.gnu.org/bugs.html> for instructions. > > But I cannot reduce that or debug that because I don't have the source to > SPEC. This is arguably a bug in the code to walk immediate uses; if a statement has multiple uses of the same SSA_NAME and you modify the statement during the imm-uses walk, there are cases where the imm-uses walk will miss the second use within the statement. The net result in this particular case is we fail to propagate away a use (because it wasn't visited due to the bug noted above), we then proceed to remove the SSA_NAME (as all its uses should have been removed). Andrew is aware of the problem and we kicked around some ideas for how to resolve it long term. I've got a couple of short-term workarounds that I'm testing. jeff -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26806