pointer to an elment in a stl vector

[Eric]

Say I have vector<int> tmp. I then call a function that needs a
pointer to an int in tmp. Is it wise to pass the function &(tmp)?
If the vector increases in size could it invalidate that pointer?

 

[Flzw]

Say I have vector<int> tmp. I then call a function that needs a
pointer to an int in tmp. Is it wise to pass the function &(tmp)?
If the vector increases in size could it invalidate that pointer?

not if you stick to adding elements, if you plan on erasing some, you
shouldn't use it, switching to list might help.

 

[Kai-Uwe Bux]

Say I have vector<int> tmp. I then call a function that needs a
pointer to an int in tmp. Is it wise to pass the function &(tmp)?

Yes. AFAIK, it is blessed by the standard.

If the vector increases in size could it invalidate that pointer?

Yes. The vector might be reallocated to accommodate for new elements.
This will invalidate all iterators and pointers derived from iterators.


Best

Kai-Uwe Bux

 

[Jeff Flinn]

Say I have vector<int> tmp. I then call a function that needs a
pointer to an int in tmp. Is it wise to pass the function &(tmp)?
If the vector increases in size could it invalidate that pointer?

not if you stick to adding elements, if you plan on erasing some, you

Wrong! std::vector:ush_back CAN cause invalidation, and most certainly
will if the capacity of the vector is insufficient.

shouldn't use it, switching to list might help.

Jeff F

 

[Rolf Magnus]

Say I have vector<int> tmp. I then call a function that needs a
pointer to an int in tmp. Is it wise to pass the function &(tmp)?

Yes. AFAIK, it is blessed by the standard.

If the vector increases in size could it invalidate that pointer?

Yes. The vector might be reallocated to accommodate for new elements.
This will invalidate all iterators and pointers derived from
iterators.

And of course also pointers not derived from iterators. It might
invalidate all pointers to any elements of the vector.