PVS-Studio warning V519 for Firefox

JS_PUBLIC_API(JSBool)
JS_GetValidFrameCalleeObject(JSContext *cx, JSStackFrame *fp,
                             jsval *vp)
{
    Value v;

    if (!Valueify(fp)->getValidCalleeObject(cx, &v))
        return false;
    *vp = v.isObject() ? v : JSVAL_VOID;
    *vp = v;
    return true;
}

This suspicious code was found in Firefox project by PVS-Studio static code analyzer.
Warning message is:
V519 The '* vp' variable is assigned values twice successively. Perhaps this is a mistake. Check lines: 711, 712. jsdbgapi.cpp 712

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/