Can you allocate an array with something equivalent to make_shared?

c++ c++11 shared-ptr make-shared
Josh Elias picture Josh Elias · Dec 10, 2012 · Viewed 17.8k times · Source 
buffer = new char[64];
buffer = std::make_shared<char>(char[64]); ???

Can you allocate memory to an array using make_shared<>()?

I could do: buffer = std::make_shared<char>( new char[64] );

But that still involves calling new, it's to my understanding make_shared is safer and more efficient.

Answer

Cubbi picture Cubbi · Dec 10, 2012

The point of make_shared is to incorporate the managed object into the control block of the shared pointer,

Since you're dealing with C++11, perhaps using a C++11 array would satisfy your goals?

#include <memory>
#include <array>
int main()
{
    auto buffer = std::make_shared<std::array<char, 64>>();
}

Note that you can't use a shared pointer the same way as a pointer you'd get from new[], because std::shared_ptr (unlike std::unique_ptr, for example) does not provide operator[]. You'd have to dereference it: (*buffer)[n] = 'a';

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