Compiler Warning (level 4) C4201

 

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The latest version of this topic can be found at Compiler Warning (level 4) C4201.

nonstandard extension used : nameless struct/union

Under Microsoft extensions (/Ze), you can specify a structure without a declarator as members of another structure or union. These structures generate an error under ANSI compatibility (/Za).

// C4201.cpp  
// compile with: /W4  
struct S  
{  
   float y;  
   struct  
   {  
      int a, b, c;  // C4201  
   };  
} *p_s;  
  
int main()  
{  
}  

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