Re: Problem with breakpoint addresses

[Mark Kettenis <mark.kettenis@xs4all.nl>]

> From: Michael Snyder <Michael.Snyder@palmsource.com>
> Date: Fri, 13 Oct 2006 11:38:49 -0700
> 
> On Fri, 2006-10-13 at 09:19 +0100, Andrew STUBBS wrote:
> > Michael Snyder wrote:
> > > What's the size of $r1, and what's the size of an address?
> > > By converting $r1 to an address, you're applying an implied cast.
> > > If that doesn't give the expected result (eg. because $r1 is signed),
> > > then you need to use an explicit cast.
> > 
> > Registers are 32 bit, addresses are 32 bit. It's just something in GDB 
> > that uses 64 bit. It might be because sh-elf also supports sh64.
> > 
> > In any case, it is successfully setting the breakpoint and then failing 
> > to recognise it when it is hit. That isn't the behaviour I would like. 
> > If it totally failed to set it then giving the cast might be fair 
> > enough, if the user thought addresses were 64 bit.
> 
> Hmmm.  Well, gdb's internal representation of a target address is
> a typedef COREADDR, and usually it equates to a long long (64 bits).

Actually, in many cases it isn't.  If you're on a 32-bit host and
configure for a purely 32-bit target, CORE_ADDR will be a 32-bit type.

> Seems like, if we know that for a given architecture, an actual
> target address is only 32 bits, we should always make sure to 
> save only 32 bits into a COREADDR.

Indeed.  This is basically what I suggested to Jan to solve his
problem.

Mark