pvanhoof@schtrumpf:~/repos/gnome/gobject-introspection/trunk/tests/invoke$ gdb ../../tools/.libs/g-idl-compiler 
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This GDB was configured as "i486-linux-gnu"...
Using host libthread_db library "/lib/tls/i686/cmov/libthread_db.so.1".
(gdb) break g_log
Function "g_log" not defined.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (g_log) pending.
(gdb) set args ./testfns.xml -o testfns-metadata.c
(gdb) run
Starting program: /home/pvanhoof/repos/gnome/gobject-introspection/trunk/tools/.libs/g-idl-compiler ./testfns.xml -o testfns-metadata.c
Breakpoint 2 at 0xb7eb6f66
Pending breakpoint "g_log" resolved

Breakpoint 2, 0xb7eb6f66 in g_log () from /usr/lib/libglib-2.0.so.0
(gdb) bt
#0  0xb7eb6f66 in g_log () from /usr/lib/libglib-2.0.so.0
#1  0xb7eb706b in g_return_if_fail_warning () from /usr/lib/libglib-2.0.so.0
#2  0x0804e171 in g_idl_compiler_write_string (ctx=0x8052720, str=0x0) at gidlcompilercontext.c:399
#3  0x0804e8cf in write_compiled (ctx=0x805b400, compiled=0x805d500, shlib=0x0, err=0xbfe9d494) at gidlcompilercontext.c:223
#4  0x0804ebf2 in g_idl_compiler_context_finalize (ctx=0x805b400, stream=0x805d500, shlib=0x0, error=0xbfe9d494) at gidlcompilercontext.c:355
#5  0x0804a571 in main (argc=134589776, argv=0x805a3b0) at compiler.c:196
(gdb)