Subject: Re: gdb over ktrace
To: None <>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-kern
Date: 04/13/2000 17:20:27
>>         int *p;
>>         p = 0;
>>         *p = 100;
> ??? Aren't you supposed to malloc space, rather than just arbitrarily
> start accessing it?  You're stepping on whatever is in page 0...

Do we have any ports that have anything mapped at address zero?  I
didn't *think* we did...

...and if I might switch to my language-lawyer hat for a moment,
assuming that indirecting through a nil pointer accesses "page 0" is a
rather machine-dependent assumption.  (Do we have any port which either
doesn't have a "page 0" or uses a nil-pointer representation that
doesn't point there?  I suspect not, in which case this is a
theoretical nitpick only.)

Of course, whether or not we have anything at address zero on the port
in question, it's hardly reasonable for a ktraced gdb to lock up when
such an access is attempted by the program being debugged.

					der Mouse
