Re: [RFC/RFA] gdb.cp/classes.exp: Don't try to print local variable out of scope

[Daniel Jacobowitz <drow@false.org>]

On Tue, Mar 09, 2004 at 10:05:29PM -0500, Daniel Jacobowitz wrote:
> Think about this for a moment.  I'm going to give addresses so that I
> can be more precise.
> 
> 0x10 <stuff>: ret		stuff(int) { }
> 0x20 <main>: push		main() {
> 0x21 <main+1>: push			{
> 0x22 <main+2>: move arg1, i			stuff(i)
> 0x23 <main+3>: call stuff			  "
> 0x24 <main+4>: pop			}
> 0x25 <main+5>: pop		}
> 0x26 <main+6>: ret		"
> 
> The inner scope is probably <main+2> to <main+3> inclusive.
> 
> Suppose PC == 0x10.  We backtrace.  Look at main; saved PC is 0x24.  We
> want an address in the block.  We subtract 1.  OK, saved addr-in-block
> is 0x23.  'i' is in scope.
> 
> Suppose PC == 0x24.  Shouldn't this be the same?  For the purposes of
> looking at local variables, aren't we still in the the block?
> 
> Suppose PC was 0x24 and we got a signal.  Ditto.
> 
> Suppose PC == 0x20 and we get a signal.  Obviously we don't want to
> change the behavior of this.

BTW, my proposed replacement is woefully inaccurate, which I should
have realized before posting.  I do not have a good solution to this
problem without actually turning back time :)

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer