(set (reg:SI ) (scratch:SI)) unrecognizable insn

["Kim, Eunchan" <helpbygrace at gmail dot com>]

Hello everyone.

Here is Thanksgiving day. Everyone went to hometown. But still i'm
porting gcc. :(

anyway, while i'm compiling libgcc, i got a error message.

>>-----------
../../../../sdk/gcc-4.3.3/libgcc/../gcc/unwind-dw2.c: In function
‘uw_install_context_1’:
../../../../sdk/gcc-4.3.3/libgcc/../gcc/unwind-dw2.c:1532: error:
unrecognizable insn:
(insn 217 80 81 14
../../../../sdk/gcc-4.3.3/libgcc/../gcc/unwind-dw2.c:1503 (set (reg:SI
1 r1)
        (scratch:SI)) -1 (nil))
../../../../sdk/gcc-4.3.3/libgcc/../gcc/unwind-dw2.c:1532: internal
compiler error: in extract_insn, at recog.c:1990
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.
--------------<<

the statement is memcpy in unwind-dw2.c:1503

>>------------ unwind-dw2.c:1500-1505
      if (dwarf_reg_size_table[i] == sizeof (_Unwind_Word))
        {
          w = (_Unwind_Internal_Ptr) t;
          memcpy (c, &w, sizeof (_Unwind_Word));
        }
      else
-----------------<<

memcpy is just a function call. so i can not understand why the
compiler try to set some value into register.

Also, i've known that (scratch:m ) is used with clobber RTL. But
scratch is used without (clobber ) in the error message.

Do i specify this RTL into machine description file? or... did i write
something wrong ?

-- Eunchan