Re: warning C4238 : cast reference in void*

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Alex Blekhman wrote:
Eric wrote:
CString foo2(CString aString)
{
return aString;
}
void* foo(CString &aString)
{
return (void*)&foo2(aString); //give C4238 warning
}
int main()
{
CString aString;
void* ptr = foo(aString);
}

foo2 returns temporary _copy_ of CString. So, you're trying
to return an address of temporary object. This code will
crash at runtime.

Sorry all, I understand that local variable are temporary objet. My
question was more about the warning C4238 and the class rvalue, lvalue
issue.

why void* ptr = &foo2(aString) give this warning ?

Regards,
Eric

.

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