/tmp/branch/objdir/gcc/xgcc -B/tmp/branch/objdir/gcc/ -nostdinc -B/tmp/branch/objdir/
xstormy16-elf/newlib/ -isystem /tmp/branch/objdir/xstormy16-elf/newlib/targ-include -
isystem /tmp/branch/combined/newlib/libc/include -B/usr/local/xstormy16-elf/bin/ -B/usr/
local/xstormy16-elf/lib/ -isystem /usr/local/xstormy16-elf/include -L/tmp/branch/objdir/ld -c 
-DSkip_f2c_Undefs -DAllow_TYQUAD -I. -I../../../../combined/libf2c/libI77 -I.. -I../../../../
combined/libf2c/libI77/.. -DHAVE_CONFIG_H -W -Wall -O2 -g -O2 ../../../../combined/libf2c/
libI77/iio.c -o iio.o
../../../../combined/libf2c/libI77/iio.c: In function `c_si':
../../../../combined/libf2c/libI77/iio.c:67: error: insn does not satisfy its constraints:
(insn 185 125 126 7 (nil) (set (reg:SI 7 r7 [78])
        (mem/s:SI (plus:HI (reg/v/f:HI 10 r10 [25])
                (const_int 16 [0x10])) [5 <variable>.icirnum+0 S4 A16])) 6 {*movsi_internal} (nil)
    (nil))
../../../../combined/libf2c/libI77/iio.c:67: internal compiler error: in 
reload_cse_simplify_operands, at reload1.c:8345
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.
make[2]: *** [iio.lo] Error 1
make[2]: Leaving directory `/tmp/branch/objdir/xstormy16-elf/libf2c/libI77'
make[1]: *** [i77] Error 2
make[1]: Leaving directory `/tmp/branch/objdir/xstormy16-elf/libf2c'
make: *** [all-target-libf2c] Error 2

Here's the reduced failing testcase:

typedef __g77_integer flag;
typedef __g77_integer ftnint;

typedef struct
{ flag icierr;
        char *iciunit;
        ftnint icirlen;
        ftnint icirnum;
} icilist;

extern char *f__icptr;
char *f__icend;

void
c_si (icilist * a)
{
  f__icend = f__icptr + a->icirlen * a->icirnum;