Function xmlXPathCompareValues 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn xmlXPathCompareValues(
    ctxt: *mut c_void,
    inf: c_int,
    strict: c_int,
) -> c_int

int xmlXPathCompareValues(xmlXPathParserContextPtr ctxt, int inf, int strict).

inf/strict encode the operator: <=(1,1), <==(1,0), >=(0,1), >==(0,0). Returns the comparison result without pushing (upstream callers push the boolean themselves).