[ECOS] No stack frames in gdb

[lunn@ma.tech.ascom.ch (Andrew Lunn)]

I've a problem with gdb. It does not show the stack frames. It can
tell you what function you are in, but not what function calls are
nested to get where you are.

bash-2.02$ ppcgdb mtest.exe
GNU gdb 4.17-ecosSWtools-981021
Copyright 1998 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.  This version of GDB is supported
for customers of Cygnus Solutions.  Type "show warranty" for details.
This GDB was configured as "--host=i586-cygwin32 --target=powerpc-eabi"...
(gdb) psim
Size of register r0 (0) incorrect (1 instead of 4))Connected to the simulator.
Breakpoint 1 at 0x83868: file //d/cygnus/ecos-1.1/packages/infra/v1_1/src/buffer.
cxx, line 707.
(gdb) break main
Breakpoint 2 at 0x80324: file mtest.c, line 14.
(gdb) run
Starting program: /h/aplett/mbuf/mtest.exe

Breakpoint 2, main () at mtest.c:14
14        mbinit();
(gdb) s
mbinit () at upic_mbuf.c:64
64              mmbfree = NULL; mclfree = NULL;
(gdb) s
65              m_mballoc(NMB_INIT);
(gdb) s
m_mballoc (nmb=128) at upic_mbuf.c:82
82              nbytes = (nmb * MSIZE);
(gdb) where
#0  m_mballoc (nmb=128) at upic_mbuf.c:82
(gdb)

Here i am three functions deep, but it only shows the current
function. Do i need to turn on some configuration option so that stack
frame GBD understands are be used?

	Thanks
		Andrew