strcpy doesn't crash despite not enough char array elements

[HalcyonDaze]

Why doesn't strcpy crash in the following sequence? I have declared a new char array with zero elements into which I am copying 5 characters.

#include <iostream>

char* buffer = new char[0];
strcpy(buffer, "Hello");
cout << buffer << endl;	

[JLBorges]

Undefined behaviour does not necessarily result in a crash.
Though, we would all be better off, if it did.