breakpoint for accessing memory location

[Daniel Jacobowitz]

On Thu, Oct 19, 2006 at 10:10:46PM +0200, Erik Leunissen wrote:
> Hi,
> 
> I've got a shared lib that I programmed to store some data on the heap 
> in order to retrieve them later. The main program which loads the shared 
> lib appears to overwrite that location in memory, before the next time I 
> want to use it (which is weird because the main program shouldn't have a 
> clue about this particular action of the shared lib).
> 
> So, in order to find out which part of the main program is being nasty, 
> I want to set some kind of breakpoint that alerts me whenever that 
> memory location is being written to.
> 
> Is that possible using gdb?
> 
> 
> (P.S. In the manual, I found the gdb command [break *address], but from 
> its behaviour, I think it's meant to do something different from what I 
> want.)

Take a look at "watchpoints" in the manual.  They should be exactly
what you need.

-- 
Daniel Jacobowitz
CodeSourcery