Question

For the Standard allocator interface for use in, say, std::vector, is re-allocation supported? I have a rather specific use-case in which being able to realloc directly would be much more efficient than allocating, moving, and freeing.

Edit: Sorry- I have absolutely no intention of calling the actual realloc, I meant a function with those semantics. Effectively, I’m allocating off a stack in the background, and if I allocate more off the stack, then I can’t free the memory underneath it, which is a total waste because there’s no need to allocate again anyway as there’s plenty of contiguous free space available. Thus, if I could be asked to reallocate in a single step, then I could avoid having to firstly, allocate some stuff and waste some memory, and secondly, move all the contents of the vector.

Answer 1

We tried but failed:

http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1953.html

http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n2045.html

Edit: I know what you meant. 😉