------- Comment #1 from pcarlini at suse dot de  2007-05-24 14:01 -------
(In reply to comment #0)

> If I change the assignments to
> 
>             int x = build_recursive(n-1);
>             int y = build_recursive(n-1);
>             b[i].left = x;
>             b[i].right = y;
> 
> there is no segmentation fault anymore. It seems to me the original
> code has the b[i] value cached, hence, during the assignment to
> b[i].right, it uses old b[i] which may be invalidated after
> push_back() due to resize.

Right, the problem is that build_recursive does a push_back, which reallocates
the vector, and when it returns the original b[i] is not pointing to vector
memory anymore. This kind of code is clearly invalid, may work by chance on an
implementation which pre-allocates at start some capacity, but will fail at
some   large size anyway.


-- 

pcarlini at suse dot de changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32068

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