[Bug regression/61516] New: [4.10 Regression]: build fails on auto-inc-dec.c or libgcc2.c with obvious patch

["hp at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61516

            Bug ID: 61516
           Summary: [4.10 Regression]: build fails on auto-inc-dec.c or
                    libgcc2.c with obvious patch
           Product: gcc
           Version: 4.10.0
               URL: http://gcc.gnu.org/ml/gcc-patches/2014-06/msg01200.htm
                    l
            Status: UNCONFIRMED
          Keywords: build, ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: regression
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hp at gcc dot gnu.org
                CC: rsandifo at gcc dot gnu.org
              Host: x86_64-unknown-linux-gnu
            Target: cris-axis-elf

Created attachment 32945
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=32945&action=edit
cc1 -fpreprocessed libgcc2.i -g -O2 -fbuilding-libgcc -fno-stack-protector
-fvisibility=hidden -o libgcc2.s

A patch in the revision range (last_known_working:first_known_failing)
(211677:211684) caused the build for cris-elf (and likely all autoincdec
targets) to fail as follows:


/tmp/hpautotest-gcc0/gcc/gcc/auto-inc-dec.c
/tmp/hpautotest-gcc0/gcc/gcc/auto-inc-dec.c: In function 'void
merge_in_block(int, basic_block_def*)':
/tmp/hpautotest-gcc0/gcc/gcc/auto-inc-dec.c:1442: error: 'uid'
was not declared in this scope
make[2]: *** [auto-inc-dec.o] Error 1

With the patch in the referenced URL, the breakage is moved to building libgcc:

/expvol/pp_slask/hp/break0615/tmp/break0615/gccobj/./gcc/xgcc
-B/expvol/pp_slask/hp/break0615/tmp/break0615/gccobj/./gcc/ -nostdinc
-B/expvol/pp_slask/hp/break0615/tmp/break0615/gccobj/cris-elf/newlib/ -isystem
/expvol/pp_slask/hp/break0615/tmp/break0615/gccobj/cris-elf/newlib/targ-include
-isystem /expvol/pp_slask/hp/break0615/tmp/break0615/gcc/newlib/libc/include
-B/expvol/pp_slask/hp/break0615/tmp/break0615/gccobj/cris-elf/libgloss/cris
-L/expvol/pp_slask/hp/break0615/tmp/break0615/gccobj/cris-elf/libgloss/libnosys
-L/expvol/pp_slask/hp/break0615/tmp/break0615/gcc/libgloss/cris
-B/expvol/pp_slask/hp/break0615/tmp/break0615/pre/cris-elf/bin/
-B/expvol/pp_slask/hp/break0615/tmp/break0615/pre/cris-elf/lib/ -isystem
/expvol/pp_slask/hp/break0615/tmp/break0615/pre/cris-elf/include -isystem
/expvol/pp_slask/hp/break0615/tmp/break0615/pre/cris-elf/sys-include    -g -O2
-march=v8 -mbest-lib-options -O2  -g -O2 -DIN_GCC  -DCROSS_DIRECTORY_STRUCTURE 
-W -Wall -Wwrite-strings -Wcast-qual -Wstrict-prototypes -Wmissing-prototypes
-Wold-style-definition  -isystem ./include   -g -DIN_LIBGCC2 -fbuilding-libgcc
-fno-stack-protector -Dinhibit_libc  -I. -I. -I../../.././gcc
-I/expvol/pp_slask/hp/break0615/tmp/break0615/gcc/libgcc
-I/expvol/pp_slask/hp/break0615/tmp/break0615/gcc/libgcc/.
-I/expvol/pp_slask/hp/break0615/tmp/break0615/gcc/libgcc/../gcc
-I/expvol/pp_slask/hp/break0615/tmp/break0615/gcc/libgcc/../include 
-DHAVE_CC_TLS -DUSE_EMUTLS -o __gcc_bcmp.o -MT __gcc_bcmp.o -MD -MP -MF
__gcc_bcmp.dep -DL__gcc_bcmp -c
/expvol/pp_slask/hp/break0615/tmp/break0615/gcc/libgcc/libgcc2.c
-fvisibility=hidden -DHIDE_EXPORTS
/expvol/pp_slask/hp/break0615/tmp/break0615/gcc/libgcc/libgcc2.c: In function
'__gcc_bcmp':
/expvol/pp_slask/hp/break0615/tmp/break0615/gcc/libgcc/libgcc2.c:2105:1:
internal compiler error: Segmentation fault
 }
 ^
0x9179b5 crash_signal
    /expvol/pp_slask/hp/break0615/tmp/break0615/gcc/gcc/toplev.c:337
0xbe23d0 merge_in_block
    /expvol/pp_slask/hp/break0615/tmp/break0615/gcc/gcc/auto-inc-dec.c:1427
0xbe23d0 execute
    /expvol/pp_slask/hp/break0615/tmp/break0615/gcc/gcc/auto-inc-dec.c:1522
Please submit a full bug report,
with preprocessed source if appropriate.


A gdb session shows that the segv is on line 1427:
          FOR_EACH_INSN_INFO_DEF (def, insn_info)
            {
=>            reg_next_use[DF_REF_REGNO (def)] = NULL;
              reg_next_inc_use[DF_REF_REGNO (def)] = NULL;
              reg_next_def[DF_REF_REGNO (def)] = insn;
            }

(gdb) p def
$5 = (df_ref) 0xafafafafafafafaf
(gdb) p *insn_info
$6 = {insn = 0x0, defs = 0xafafafafafafafaf, uses = 0xafafafafafafafaf,
  eq_uses = 0xafafafafafafafaf, mw_hardregs = 0xafafafafafafafaf,
  luid = -1347440721}
(gdb)

Preprocessed code is attached.

Author of suspect patches in revision range CC:ed.