H is not used here, the array is dealt with directly. Eliminates warning.

src/pgsql_binary.erl

@@ -66,7 +66,7 @@ encode_array(Type, [H | _] = Array, NDims, Lengths) when not is_list(H) ->
     F = fun(E, Len) -> {encode(Type, E), Len + 1} end,
     {Data, Len} = lists:mapfoldl(F, 0, Array),
     {Data, {NDims + 1, [Len | Lengths]}};
-encode_array(uuid, [H | _] = Array, NDims, Lengths) ->
+encode_array(uuid, [_H | _] = Array, NDims, Lengths) ->
     F = fun(E, Len) -> {encode(uuid, E), Len + 1} end,
     {Data, Len} = lists:mapfoldl(F, 0, Array),
     {Data, {NDims + 1, [Len | Lengths]}};