compiler-warning-level-4-c4458.md

description	title	ms.date	f1_keywords	helpviewer_keywords	ms.assetid
Learn more about: Compiler Warning (level 4) C4458	Compiler Warning (level 4) C4458	11/04/2016	C4458	C4458	7bdaa1b1-0caf-4d68-98c4-6bdd441c23fb

Compiler Warning (level 4) C4458

declaration of 'identifier' hides class member

The declaration of identifier in the local scope hides the declaration of the identically-named identifier at class scope. This warning lets you know that references to identifier in this scope resolve to the locally declared version, not the class member version, which may or may not be your intent. To fix this issue, we recommend you give local variables names that do not conflict with class member names.

Example

The following sample generates C4458 because the parameter x and the local variable y in member_fn have the same names as data members in the class. To fix this issue, use different names for the parameters and local variables.

// C4458_hide.cpp
// compile with: cl /W4 /c C4458_hide.cpp

struct S {
    int x;
    float y;
    void member_fn(long x) {   // C4458
        double y;  // C4458
        y = x;
        // To fix this issue, change the parameter name x
        // and local name y to something that does not
        // conflict with the data member names.
    }
} s;