Using malloc instead of new, and calling the copy constructor when the object is created

Question

I wanted to try out TBB\'s scalable_allocator, but was confused when I had to replace some of my code. This is how allocation is done with the allocator:

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Answer 1

The parameter to allocate() is the number of objects, not the size in bytes. You then call the allocator's construct() function to construct the object.

scalable_allocator sa;
SomeClass* s = sa.allocate(1);
sa.construct(s, SomeClass());
// ...
sa.destroy(s);
sa.deallocate(s);

If want to use it with a standard library container or other std allocator aware type, simply give it the allocator type.

std::vector> v;