Memory Write Breakpoint in vc7

[Anil Aksay]

I need to put a breakpoint when a particular memory location is
written. To be more specific I want to know when 0 is written onto that
memory location. Is there a way to do it in vc7?

Regards,

Anil.

[David Lowndes]

Re: Memory Write Breakpoint in vc7

>I need to put a breakpoint when a particular memory location is[color=blue]
>written. To be more specific I want to know when 0 is written onto that
>memory location. Is there a way to do it in vc7?[/color]

Anil,

Use the Data tab page of the New Breakpoint dialog.

Dave

[Anil Aksay]

Re: Memory Write Breakpoint in vc7

Data tab page requires a variable in some context. There is a local
variable in some function but it is overwritten by someone else. I've
debugged and everytime that function is called variable has the same
address. Code is as follows:

int variable = a/b;
ASSERT(variable );
c = d / variable;

when assert break the application, I've checked that a/b result is 14,
however the variable has 0 inside. The address of the variable is
0x975f328. (everytime we enter that code segment the address is same).
And assert only stops occasionally.

So I want to put a breakpoint when that variable is overwritten by
another thread.

In the new Data tab page there are following items:

Variable:
Context:
Condition:

I've tried to write something like:

(* ((int *)(0x975f328))) == 0

in either condition or variable edit box but it refuses that it is not
proper.

What can I do about it?

Anil.



-David Lowndes'in mesaji: > >I need to put a breakpoint when a
particular memory location is[color=blue][color=green]
> >written. To be more specific I want to know when 0 is written onto that
> >memory location. Is there a way to do it in vc7?[/color]
>
> Anil,
>
> Use the Data tab page of the New Breakpoint dialog.
>
> Dave[/color]

[Anil Aksay]

Re: Memory Write Breakpoint in vc7

actually i've managed to put the breakpoint but since it is a local
variable address.. many places in the application use that memory quite
often. now i need to find a better way to find who actually wrote after
variable is defined and before its context finishes.

any suggestions?

-Anil Aksay'in mesaji: > Data tab page requires a variable in some
context. There is a local[color=blue]
> variable in some function but it is overwritten by someone else. I've
> debugged and everytime that function is called variable has the same
> address. Code is as follows:
>
> int variable = a/b;
> ASSERT(variable );
> c = d / variable;
>
> when assert break the application, I've checked that a/b result is 14,
> however the variable has 0 inside. The address of the variable is
> 0x975f328. (everytime we enter that code segment the address is same).
> And assert only stops occasionally.
>
> So I want to put a breakpoint when that variable is overwritten by
> another thread.
>
> In the new Data tab page there are following items:
>
> Variable:
> Context:
> Condition:
>
> I've tried to write something like:
>
> (* ((int *)(0x975f328))) == 0
>
> in either condition or variable edit box but it refuses that it is not
> proper.
>
> What can I do about it?
>
> Anil.
>
>
>
> -David Lowndes'in mesaji: > >I need to put a breakpoint when a
> particular memory location is[color=green][color=darkred]
> > >written. To be more specific I want to know when 0 is written onto that
> > >memory location. Is there a way to do it in vc7?[/color]
> >
> > Anil,
> >
> > Use the Data tab page of the New Breakpoint dialog.
> >
> > Dave[/color][/color]

[David Lowndes]

Re: Memory Write Breakpoint in vc7

>any suggestions?

If you're not already doing these, I'd ensure I had all the compiler
run-time checks enabled, compile at the highest warning level, and if
they don't show anything, try a product such as bounds checker or
purify.

Dave
--
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