Debugging multi-threaded programmes

Hello everyone,

Is there an extensive use of ddd over gdb for debugging multi-threaded
applications, or in other words how reliable or easy is it to do this,
especially for hard real time applications in Linux user space?

I have had a lot of difficulties doing this and I sincerely hope someone can
help. I am having a range of problems with ddd version 3.3.11 on top of gdb
version 6.3.0.0-1.122rh. The most annoying problem is local variables not
known to the gdb - I get "No symbol "fred" in current context" although that
may be a gdb problem. I have compiled my programme with: 

-O2 -g -ggdb -gstabs+ 

but still no luck! I would be most grateful if someone could help.

Aref