On Tue, Jun 13, 2006 at 08:28:33PM -0700, Trent Piepho wrote: > On Wed, 14 Jun 2006, Stephen Thorne wrote: > > > On 6/14/06, Trent Piepho <xyzzy at speakeasy.org> wrote: > > > p_mapchars isn't a string, it's just two characters with no null termination. > > > You can't print it with %s. > > > > You can't? A quick grep in the source shows 58 occurances of printing > > p_mapchars with %s. > > All bugs. Look at struct.h: > ./struct.h: char p_mapchars; /* Cache for map window image */ Actually, a grep shows: include/struct.h: char p_mapchars; /* Cache for map window image, i.e. "R0" */ ntserv/main.c: me->p_mapchars = 'X'; ntserv/main.c: me->p_mapchars = shipnos[pno]; ntserv/main.c: me->p_mapchars = '\0'; And the various *printf's are of the form: sprintf(k->p_longname, "%s (%s)", k->p_name, k->p_mapchars); which are quite legitimate and not bugs at all since the p_mapchars is NULL teriminated. The robot code does use a 2 byte local mapchars: inl.c: char mapchars; But uses strncpy to copy the local mapchars to the player struct: inl.c: STRNCPY(winners[k].mapchars, j->p_mapchars, 2); I've not bothered looking through the code any further at the moment, and there may very well be bugs related to improper usage of a non-NULL terminated mapchars, however I'd have to disagree that all 58 occurances of printing p_mapchars with %s are bugs. As for GCC tolerating non-NULL-terminated strings, that's just silly conjecture. The compiled program will print characters until it reaches a NULL or an exception condition at which point a SIGSEGV/SIGILL/etc signal is raised depending on context. It is possible due to sheer luck that buggy *printf code may function correctly as intended because of compiler behavior in zeroing out unused memory segments (very common in debug mode), including the unused structure padding bytes in X-byte aligned architectures. However, the likelihood of such buggy code to go undiscovered for years (like Vanilla) is rather small.