Compiler Warning (level 4) C4211


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The latest version of this topic can be found at Compiler Warning (level 4) C4211.

nonstandard extension used : redefined extern to static

With the default Microsoft extensions (/Ze), you can redefine an extern identifier as static.

// C4211.c  
// compile with: /W4  
extern int i;  
static int i;   // C4211  
int main()  

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

(NOTINBUILD)Static Storage-Class Specifiers