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From: Andy Fan <zhihui.fan1213@gmail.com>
Date: Wed, 1 Apr 2020 07:53:40 +0800
Message-ID: <CAKU4AWr=G6yOA9DAjKcTs9KOGhfzjjm9bQSEH=u=9aP3XNmfLQ@mail.gmail.com>
Subject: Re: Detect uninitialized memory in gdb
To: Christian Biesinger <cbiesinger@google.com>
Cc: gdb@sourceware.org
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On Wed, Apr 1, 2020 at 2:48 AM Christian Biesinger <cbiesinger@google.com>
wrote:

> On Tue, Mar 31, 2020 at 1:08 AM Andy Fan via Gdb <gdb@sourceware.org>
> wrote:
> >
> > Greetings.
> >
> > Suppose I have the following codes:
> >
> > struct X { ... };
> >
> > void g(struct X *x_p);
> >
> > void f()
> > {
> >    struct X x_var;
> >    g(&x_var);
> > }
> >
> > In the function of g,  I want to check the data where x_p point to,
> > however it is possible that it is not initialized like above code. So
> > do we have a way to detect that the memory x_p point to is not
> > initialized or not in gdb?
>
> No, it's not really possible with GDB. You want a tool like Valgrind
> or Address Sanitizer.
>
> Thank you for your reply Christian.   Just because I want to call gdb
script after I know it is initialized,  so Valgrind is not my option now.

Best Regards
Andy Fan