compiler-warning-level-1-c4537.md

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Learn more about: Compiler Warning (level 1) C4537	Compiler Warning (level 1) C4537	08/27/2018	C4537	C4537	9454493c-d419-475e-8f35-9c00233c9329

Compiler Warning (level 1) C4537

'object' : 'operator' applied to non-UDT type

Remarks

A reference was passed where an object (user-defined type) was expected. A reference is not an object, but inline assembler code is not able to make the distinction. The compiler generates code as though object were an instance.

Example

The following sample generates C4537 and shows how to fix it:

// C4537.cpp
// compile with: /W1 /c
// processor: x86
struct S {
    int member;
};

void f1(S &s) {
    __asm mov eax, s.member;   // C4537
    // try the following code instead
    // or, make the declaration "void f1(S s)"
    /*
    mov eax, s
    mov eax, [eax]s.member
    */
}