John Love-Jensen writes: > Hi Nick, > > NCR is not a symbol. It is part of a preprocessor directive. Yes, but if I do: (gdb) inf source Current source file is myprog.c Compilation directory is /home/nickrob Located in /home/nickrob/myprog.c Contains 96 lines. Source language is c. Compiled with DWARF 2 debugging format. Includes preprocessor macro info. ^^^^^^^^ It tells me that the executable should have information about that directive. GDB is GNU gdb Red Hat Linux (6.1post-1.20040607.43rh) but I get the same result with GDB from the CVS repository, which worked with an earlier GCC (3.2 something on Mandrake 9), so I'm pretty sure that the problem doesn't lie with GDB. Nick