Returning pointer to a local/stack variable in C++

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I am confused on this functionx tutorial....

<a href="http://www.functionx.com/cpp/examples/returnpointer.htm">http://www.functionx.com/cpp/examples/returnpointer.htm</a>[<a href="http://www.functionx.com/cpp/examples/returnpointer.htm" target="_blank" title="New Window">^</a>]

will returning a pointer to an local object of myclass is correct? will that object destroyed on going out of function scope... confused....
I raised the question in msdn forum... still not clear...

http://social.msdn.microsoft.com/Forums/en-US/vclanguage/thread/75f14e6f-7e75-4d3a-abc0-b18514eed24c/?prof=required[^]

Posted 1-May-11 18:35pm

rajeshkanakarajan

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tolw · Answer 1 · 2011-05-01T19:01:00

I'm not sure what is unclear exactly... You seem to have gotten it right - returning pointers to local data is not safe and should be avoided. Nothing more to add really.

EDIT: To answer your second question:
IMHO the tutorial is wrong.
The copy constructor of the class will not be called.

By the way - you should not post additional questions as 'answers' - use the 'Add comment' link under existing answers to ask additional questions or comment on the answers others give you. This keeps the thread nice and clear for everyone to view :)

Alain Rist · Answer 2 · 2011-05-01T21:57:00

Solution 3

Hi,

Your ~~tutorial~~ is junk, don't trust it anywhere else.

This, and other similar changes would be correct:

double * GetSalary()
{
    static double salary = 26.48;

    return &salary;
}

cheers,
AR

Posted 1-May-11 21:57pm

Alain Rist

Comments

Olivier Levrey 2-May-11 8:16am

Agree. 5.

CPallini · Answer 3 · 2011-05-01T22:31:00

Solution 4

The tutorial is wrong: never return the address of a local object.
:-)

Posted 1-May-11 22:31pm

CPallini

Comments

Hans Dietrich 2-May-11 4:56am

Unless it's a static, like Alain says.

Olivier Levrey 2-May-11 8:17am