Seen on Ubuntu 9.10. The test case is reduced from the output of the Stalin Scheme to C compiler.
reg...@john-home:~/z/stalin-0.11$ current-gcc -c small.c -O small.c: In function f1576: small.c:86:1: error: unrecognizable insn: (insn 42 41 43 10 small.c:79 (parallel [ (set (reg:QI 79) (if_then_else:SI (unlt:SI (reg:CCFPU 17 flags) (const_int 0 [0x0])) (const_int -1 [0xffffffff]) (const_int 0 [0x0]))) (clobber (reg:CC 17 flags)) ]) -1 (nil)) small.c:86:1: internal compiler error: in extract_insn, at recog.c:2097 Please submit a full bug report, with preprocessed source if appropriate. See <http://gcc.gnu.org/bugs.html> for instructions. reg...@john-home:~/z/stalin-0.11$ cat small.c void gt_error (void); struct region19168 { union { } value; }; struct w29434 { }; struct w16638 { union { } value; }; struct w12218 { union { } value; }; struct w9140 { union { } value; }; struct w6194 { union { } value; }; struct w3457 { union { } value; }; struct w49 { unsigned tag; union { int fixnum_type; float flonum_type; } value; }; void f1576 (struct w49 a15167, struct w49 a15168, unsigned a15169, unsigned a15170, unsigned t84936, struct w49 t84939, struct w49 t84940) { struct w49 a33604; struct w49 t84937; struct w16638 t84965; switch (t84936) { case 5960: a33604 = t84937; switch (t84939.tag) { case 1048: switch (t84940.tag) { } case 1052: switch (t84940.tag) { case 1048: if (!((t84939.value.flonum_type) > (t84940.value.fixnum_type))) goto l16231; } gt_error (); } } l16231:t84965 = *((struct w16638 *) (&a15168)); } reg...@john-home:~/z/stalin-0.11$ current-gcc -v Using built-in specs. COLLECT_GCC=current-gcc COLLECT_LTO_WRAPPER=/home/regehr/z/tmp/gcc-r156271-install/libexec/gcc/i686-pc-linux-gnu/4.5.0/lto-wrapper Target: i686-pc-linux-gnu Configured with: ../configure --with-libelf=/usr/local --enable-lto --prefix=/home/regehr/z/tmp/gcc-r156271-install --program-prefix=r156271- --enable-languages=c,c++ Thread model: posix gcc version 4.5.0 20100127 (experimental) (GCC) -- Summary: ice in extract_insn, at recog.c:2097 Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: regehr at cs dot utah dot edu GCC build triplet: i686-pc-linux-gnu GCC host triplet: i686-pc-linux-gnu GCC target triplet: i686-pc-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42891