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Compiler Warning (levels 2 and 4) C4200

nonstandard extension used : zero-sized array in struct/union

A structure or union contains an array with zero size.

Level-2 warning when compiling a C++ file and a Level-4 warning when compiling a C file.

// C4200.cpp
// compile with: /W2
#include <stdio.h>
struct A {
int a[0];  // C4200
int main() {