Compiler Warning (level 4) C4289

 

For the latest documentation on Visual Studio 2017, see Visual Studio 2017 Documentation.

For the latest documentation on Visual Studio 2017, see Compiler Warning (level 4) C4289 on docs.microsoft.com. nonstandard extension used : 'var' : loop control variable declared in the for-loop is used outside the for-loop scope

When compiling with /Ze and /Zc:forScope-, a variable declared in a for loop was used after the for-loop scope.

See /Zc:forScope for information about how to specify standard behavior in for loops with /Ze.

This warning is off by default. See Compiler Warnings That Are Off by Default for more information.

The following sample generates C4289:

// C4289.cpp  
// compile with: /W4 /Zc:forScope-  
#pragma warning(default:4289)  
int main() {  
   for (int i = 0 ; ; )   // C4289  
      break;  
   i++;  
}  

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