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From: Christian Biesinger <cbiesinger@google.com>
Date: Tue, 31 Mar 2020 13:48:16 -0500
Message-ID: <CAPTJ0XEtZjsADcnXGXUb4Q5Q+xFg08yWbW2kH=wruDbapgJgbA@mail.gmail.com>
Subject: Re: Detect uninitialized memory in gdb
To: Andy Fan <zhihui.fan1213@gmail.com>
Cc: gdb@sourceware.org
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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.

Christian