Does new[] initialise an array of builtins? [duplicate]

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Operator new initializes memory to zero (4 answers)

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Does using new[] in C++ initialise the allocated array to all zeroes?

Answer 1

Does new[] initialise an array of builtins?

It depends:

int* = new int[42];   // default initialization: elements not initialized

int* = new int[42](); // value initialization: elements are zero initialized

Note the terminology: in the first example, the elements are said to be default-initialized, which for built-ins means no initialization is performed. In the second example, the elements are value-initialized, which for built-ins means zero-initialization.