gdb-6.3 debug bug

[Der Herr Hofrat]

HI !

while working on tracepoint implementation I tried turning on 
architecture code tracing with:

/* Non-zero if we want to trace architecture code.  */

#ifndef GDBARCH_DEBUG
#define GDBARCH_DEBUG 3
#endif
int gdbarch_debug = GDBARCH_DEBUG;

which compiles ok - but on execution of the so compiled gdb it crashes with

...
gdbarch_dump: DECR_PC_AFTER_BREAK # (gdbarch_decr_pc_after_break 
(current_gdbarch))
gdbarch.c:1868: internal-error: gdbarch_addr_bit: Assertion `gdbarch != NULL' 
failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n)
Create a core file of GDB? (y or n) y
Aborted


no core file is generated - and obviously gdb is not functioining - the 
like reported as offending does not seem to be the direct cause of the 
problem as it is not enabled by GDBARCH_DEBUG > 0

int
gdbarch_addr_bit (struct gdbarch *gdbarch)
{
  gdb_assert (gdbarch != NULL);
  /* Check variable changed from pre-default.  */
  gdb_assert (gdbarch->addr_bit != 0);
  if (gdbarch_debug >= 2)
    fprintf_unfiltered (gdb_stdlog, "gdbarch_addr_bit called\n");
  return gdbarch->addr_bit;
}

if I can provide any further infos let me know - to reproduce the problem
simply set #define GDBARCH_DEBUG 3 in gdb/gdbarch.c .

thx !
hofrat