Tell me about stack frames....

[Jim Blandy]

It looks like you're using a customized version of GDB 6.2, or having
GDB run a script.  For example, who is printing 'entering
dbugS12_wait'?

GDB 6.2 is old; you might try a current version of GDB.

The output from 'bt' doesn't seem to ever find a valid stack frame. 
Are you sure the program is even running, or that GDB is able to
properly read its registers?  When you print $pc, does its value look
like a reasonable code address?  Does the value of $sp seem to be a
reasonable stack address?