gcc-2.95pre: crash in loop code (validate_change)

[Jeffrey A Law]

  In message < 99052219183500.00669@ns1102.munich.netsurf.de >you write:
  > Hi,
  > 
  > the appended testcase (distilled from RH-6.0 xscreensaver) segfaults on
  > powerpc-linux-gnu, if compiled with -O2 or higher:
  > 
  > (gdb) r rorschach.i -quiet -O2 -o rorschach.s
  > Starting program: /home/fsirl/obj/cvsm/gcc/stage1/cc1 test.i -quiet -dumpba
  > se test.c -O2 -version -o test.s
  > GNU C version gcc-2.95 19990522 (prerelease) (ppc-redhat-linux) compiled by
  >  GNU C version egcs-2.91.66 19990314 (egcs-1.1.2 release).
  > 
  > Program received signal SIGSEGV, Segmentation fault.
  > 0x1a33c4c in validate_change (object=0x1be4468, loc=0x0, new=0x1bc59dc, in_
  > group=0) at ../../../egcsm/gcc/recog.c:244
  > 244       rtx old = *loc;
  > (gdb) bt
  > #0  0x1a33c4c in validate_change (object=0x1be4468, loc=0x0, new=0x1bc59dc,
  >  in_group=0) at ../../../egcsm/gcc/recog.c:244
  > #1  0x195e974 in strength_reduce (scan_start=0x1be3200, end=0x1be7158, loop
  > _top=0x0, insn_count=67, loop_start=0x1be31c8, loop_end=0x1be7158,
  >     loop_cont=0x1be7050, unroll_p=0, bct_p=0) at ../../../egcsm/gcc/loop.c:
This should be fixed now thanks to Joern and Mark.

Jeff