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The amount of overhead required by array new expressions is unspecified but ideally would be documented by quality implementations. The following compliant solution is specifically for the Clang and GNU GCC compilers, which guarantee that the overhead can be likened to for dynamic array allocations is a single value of type size_t. To verify that the assumption is, in fact, safe, the compliant solution also overloads the placement new[] operator to accept the buffer size as a third argument and verifies that it is at least as large as the total amount of storage required.
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