Re: "this" pointer get corrupted after function call

From:
Ian Collins <ian-news@hotmail.com>
Newsgroups:
comp.lang.c++
Date:
Wed, 27 Jun 2012 20:12:33 +1200
Message-ID:
<a4vtjhF91rU2@mid.individual.net>
On 06/27/12 07:39 PM, Krishs P. wrote:

On Wednesday, 27 June 2012 12:44:53 UTC+5:30, Alf P. Steinbach wrote:

On 27.06.2012 08:36, Krishs wrote:

Hi all,
   well this is pretty much confusion to me as well, but here is
scenario. I have two shared objects file and one loader executable.
   loader calls extern function in shared1 , which has one class ,
initialize it and run its method , which would call extern in shared2.
   after shared2 extern function returns, the "this" pointer get 0x00 in
A::Run(),
   any guess what would have been happened, I have using gcc version 4+
to build the project.

** loader.cpp
       - calls run_test(); in shared1.cpp

** shared1.cpp
         class A {
             public:
                  Run() { mum_tum(); doWell(); }
                  doWell() { }
         };

         extern void run_test() {
                 A *a = new A();
                 a->Run();
         }

** shared2.cpp
        extern void mum_tum() { }

thank you.


with three different method naming conventions in so short a code, plus
a question of non-reproducable behavior where even the description of
what's allegedly wrong is suspect, this is clearly a troll posting


thx for the reply . but, the code i am working with is pretty much big and complex, so I described the scenario with short pseudo code. The main problem relies when actual this pointer of "class A" get vanished after call to extern function in second shared dll. What I am concerned here is if it is case of stack corruption or something. I have checked similar case from gdb forum but no clue.


Please wrap your lines!

It looks like you problem may be windows rather than C++ related, have
you tried a windows group?

--
Ian Collins

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