Compiler Warning (level 4) C4204


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The latest version of this topic can be found at Compiler Warning (level 4) C4204.

nonstandard extension used : non-constant aggregate initializer

With Microsoft extensions (/Ze), you can initialize aggregate types (arrays, structures, unions, and classes) with values that are not constants.

// C4204.c  
// compile with: /W4  
int func1()  
   return 0;  
struct S1  
   int i;  
int main()  
   struct S1 s1 = { func1() };   // C4204  
   return s1.i;  

Such initializations are invalid under ANSI compatibility (/Za).