assertion failure in df_reg_chain_mark

[Christian Grössler]

Hi,

I'm in the process of reviving a 2 year old port and merge the changes done to 
gcc since Nov-2008 into it.

Now I'm getting an assertion failure:

In file included from ../../../src/libiberty/regex.c:638:0:
../../../src/libiberty/regex.c: In function 'byte_re_match_2_internal':
../../../src/libiberty/regex.c:7484:1: internal compiler error: in 
df_reg_chain_mark, at df-scan.c:4233
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.


This part in df_reg_chain_mark triggers the assertion:


      if (is_eq_use)
        gcc_assert ((DF_REF_FLAGS (ref) & DF_REF_IN_NOTE));
      else
        gcc_assert ((DF_REF_FLAGS (ref) & DF_REF_IN_NOTE) == 0);  <<<<---- this 
one

      if (DF_REF_NEXT_REG (ref))
        gcc_assert (DF_REF_PREV_REG (DF_REF_NEXT_REG (ref)) == ref);


Can anyone give me some hints or pointers where to look to resolve the problem?

thanks,
chris

PS: imported gcc source is from Nov-29-2010