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Date: Mon, 19 Nov 2007 08:39:00 -0000
From: "Douglas Evans" <dje@google.com>
To: "Peng Yu" <pengyu.ut@gmail.com>
Subject: Re: gdb does not print the reference to the base class members
Cc: gdb@sourceware.org
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I  believe this is gcc bug 27574.

On Nov 18, 2007 4:35 PM, Peng Yu <pengyu.ut@gmail.com> wrote:
> Hi,
>
> I try to print reference x for the following problem. But gdb does not
> print the one in class B refered to class A? Do you know how to print
> its value?
>
> Thanks,
> Peng
>
> (gdb) b 22
> Breakpoint 1 at 0x8048694: file main.cc, line 22.
> (gdb) b 14
> Breakpoint 2 at 0x8048706: file main.cc, line 14.
> (gdb) r
> Failed to read a valid object file image from memory.
>
> Breakpoint 1, main () at main.cc:22
> 22        B b(10);
> (gdb) p x
> $1 = (int &) @0xbffd86cc: 5
> (gdb) c
>
> Breakpoint 2, B (this=0xbffd86c8, a=10) at main.cc:14
> 14            std::cout << x << std::endl;
> (gdb) p x
> No symbol "x" in current context.
>
>
>
> #include <iostream>
>
> class A {
>   public:
>     A(int a) : _a(a) { }
>   protected:
>     int _a;
> };
>
> class B : public A {
>   public:
>     B(int a) : A(a) {
>       int &x = A::_a;//can not print from gdb, Line 12
>       std::cout << x << std::endl;
>     }
> };
>
>
> int main(){
>   int a = 5;
>   int &x = a;//this one can be printed in gdb, Line 22
>   B b(10);
>   std::cout << x << std::endl;
> }
>