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) 


(gdb) up
#1  0xb7eb706b in g_return_if_fail_warning () from /usr/lib/libglib-2.0.so.0
(gdb) 
#2  0x0804e171 in g_idl_compiler_write_string (ctx=0x8052720, str=0x0) at gidlcompilercontext.c:399
399       g_return_val_if_fail (str != NULL, 0);
(gdb) 
#3  0x0804e8cf in write_compiled (ctx=0x805b400, compiled=0x805d500, shlib=0x0, err=0xbfe9d494) at gidlcompilercontext.c:223
223       g_idl_compiler_write_string (ctx, shlib);
(gdb) print *ctx
$1 = {namespace_name = 0x805ad50 "test", struct_name = 0x805a3b0 "struct mdata_test", mdata_struct_fn = 0x805d1d8 "/tmp/gicomp-55727T", 
  mdata_struct = 0x805c030, mdata_init_fn = 0x805d190 "/tmp/gicomp-57727T", mdata_init = 0x805c198, string_offset = 82, 
  mdata_string_fn = 0x805c000 "/tmp/gicomp-J2727T", mdata_string = 0x805d230, strings = 0x8059a00, directory_local_entries = 8, 
  directory_entries = 8, mdata_directory_fn = 0x805c018 "/tmp/gicomp-N3727T", mdata_directory = 0x805d398, entriesdb = 0x8059a20, 
  typesdb = 0x8059a40, dtypelist = 0x0, dsignaturelist = 0x0, dconstantlist = 0x0}
(gdb) print *shlib
Cannot access memory at address 0x0
(gdb)