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