Compiler Warning (level 4) C4289
Visual Studio 2015
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The latest version of this topic can be found at Compiler Warning (level 4) C4289.
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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