Generated tests t154 and t199 from gcc.dg/compat/struct-layout-1 fail
with an ICE compiling c_compat_y_tst.o with -m64 on powerpc64-linux.
The first started failing on 20050424, the second on 20050501, and both
have failed regularly since then, but it seems to be a latent bug
because results for regression hunts don't match up with those dates.
                                                                                
I'll attach minimized test cases for both.  Here's the output I get from
today's mainline:
                                                                                
elm3b11% /opt/gcc-nightly/mline/bin/gcc -m64 -c bug_t154.c
bug_t154.c: In function ‘check13995’:
bug_t154.c:36: error: unrecognizable insn:
(insn 25 24 26 1 (set (reg:DF 130 [ D.1250+8 ])
        (subreg:DF (mem/s/j:DC (plus:DI (reg/f:DI 114 virtual-stack-vars)
                    (const_int 33112 [0x8158])) [0 <variable>.e.m+0 S16 A64])
8)) -1 (nil)
    (nil))
bug_t154.c:36: internal compiler error: in extract_insn, at recog.c:2082
                                                                                
elm3b11% /opt/gcc-nightly/mline/bin/gcc -m64 -c bug_t199.c
bug_t199.c: In function ‘check18102’:
bug_t199.c:23: error: unrecognizable insn:
(insn 29 28 30 1 (set (reg:SF 130 [ D.1239+4 ])
        (subreg:SF (mem/s/j:SC (plus:DI (reg/f:DI 114 virtual-stack-vars)
                    (const_int 56000 [0xdac0])) [0 arg2.y+0 S8 A512]) 4)) -1 (nil)
    (nil))
bug_t199.c:23: internal compiler error: in extract_insn, at recog.c:2082

-- 
           Summary: unrecognized insn for struct-layout-1 tests with complex
                    members
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: janis at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: powerpc64-linux
  GCC host triplet: powerpc64-linux
GCC target triplet: powerpc64-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21742