compiler-warning-level-1-c4218.md

description	title	ms.date	f1_keywords	helpviewer_keywords
Learn more about: Compiler Warning (level 4) C4218	Compiler Warning (level 4) C4218	11/04/2016	C4218	C4218

Compiler Warning (level 4) C4218

nonstandard extension used: must specify at least a storage class or a type

With the default Microsoft extensions (/Ze), you can declare a variable without specifying a type or storage class. The default type is int.

Example

// C4218.c
// compile with: /W4
i;  // C4218

int main()
{
}

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