silence warning

fixed_wide/src/fixed.rs

@@ -142,6 +142,8 @@ impl_additive_operator!( Fixed, BitXor, bitxor, Self );
 
 // non-wide operators.  The result is the same width as the inputs.
 
+// This macro is not used in the default configuration.
+#[allow(unused_macros)]
 macro_rules! impl_multiplicative_operator_not_const_generic {
 	( ($struct: ident, $trait: ident, $method: ident, $output: ty ), $width:expr ) => {
 		impl<const F:usize> core::ops::$trait for $struct<$width,F>{