Strange gdb behavior with optimized code

[Ludo']

Hi,

I noticed a strange behaviour of gdb when debugging code that had been
compiled with `-O2 -mpentium': when stepping, gdb sometimes seems to get lost
in the code (goes back to the same line several times for instance). I'm not
sure this is really a bug since this is probably not recommended to debug a
program that had been optimized.

Example of what gdb does:

Breakpoint 1, netfs_get_dirents (cred=0x804b958, dir=0x804b4e8, entry=0, 
    nentries=-1, data=0x11fbcec, datacnt=0x11fbcf0, bufsize=0, amt=0x11fbcf8)
    at netfs.c:139
139       curr_datap = *data;
(gdb) n
142       backend.set_curr_dir (dir);
(gdb) 
138       curr_amt = 0;
(gdb) 
142       backend.set_curr_dir (dir);
(gdb) 
139       curr_datap = *data;
(gdb) 
142       backend.set_curr_dir (dir);
(gdb) 
143       no_more = backend.skip_entries (entry);
(gdb) n
145       for (curr_entry = entry;

Notice that line 142 appears several times.

Thanks,
Ludovic.