| warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks |
| --> $DIR/fn_must_use.rs:41:5 |
| | |
| LL | #[must_use] |
| | ^^^^^^^^^^^ |
| | |
| = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release! |
| = help: `#[must_use]` can be applied to data types, foreign functions, functions, inherent methods, provided trait methods, required trait methods, traits, and unions |
| = note: requested on the command line with `-W unused-attributes` |
| |
| warning: unused return value of `need_to_use_this_value` that must be used |
| --> $DIR/fn_must_use.rs:57:5 |
| | |
| LL | need_to_use_this_value(); |
| | ^^^^^^^^^^^^^^^^^^^^^^^^ |
| | |
| = note: it's important |
| note: the lint level is defined here |
| --> $DIR/fn_must_use.rs:3:9 |
| | |
| LL | #![warn(unused_must_use)] |
| | ^^^^^^^^^^^^^^^ |
| help: use `let _ = ...` to ignore the resulting value |
| | |
| LL | let _ = need_to_use_this_value(); |
| | +++++++ |
| |
| warning: unused return value of `MyStruct::need_to_use_this_method_value` that must be used |
| --> $DIR/fn_must_use.rs:62:5 |
| | |
| LL | m.need_to_use_this_method_value(); |
| | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ |
| | |
| help: use `let _ = ...` to ignore the resulting value |
| | |
| LL | let _ = m.need_to_use_this_method_value(); |
| | +++++++ |
| |
| warning: unused return value of `EvenNature::is_even` that must be used |
| --> $DIR/fn_must_use.rs:63:5 |
| | |
| LL | m.is_even(); // trait method! |
| | ^^^^^^^^^^^ |
| | |
| = note: no side effects |
| help: use `let _ = ...` to ignore the resulting value |
| | |
| LL | let _ = m.is_even(); // trait method! |
| | +++++++ |
| |
| warning: unused return value of `MyStruct::need_to_use_this_associated_function_value` that must be used |
| --> $DIR/fn_must_use.rs:66:5 |
| | |
| LL | MyStruct::need_to_use_this_associated_function_value(); |
| | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ |
| | |
| help: use `let _ = ...` to ignore the resulting value |
| | |
| LL | let _ = MyStruct::need_to_use_this_associated_function_value(); |
| | +++++++ |
| |
| warning: unused return value of `std::cmp::PartialEq::eq` that must be used |
| --> $DIR/fn_must_use.rs:72:5 |
| | |
| LL | 2.eq(&3); |
| | ^^^^^^^^ |
| | |
| help: use `let _ = ...` to ignore the resulting value |
| | |
| LL | let _ = 2.eq(&3); |
| | +++++++ |
| |
| warning: unused return value of `std::cmp::PartialEq::eq` that must be used |
| --> $DIR/fn_must_use.rs:73:5 |
| | |
| LL | m.eq(&n); |
| | ^^^^^^^^ |
| | |
| help: use `let _ = ...` to ignore the resulting value |
| | |
| LL | let _ = m.eq(&n); |
| | +++++++ |
| |
| warning: unused comparison that must be used |
| --> $DIR/fn_must_use.rs:76:5 |
| | |
| LL | 2 == 3; |
| | ^^^^^^ the comparison produces a value |
| | |
| help: use `let _ = ...` to ignore the resulting value |
| | |
| LL | let _ = 2 == 3; |
| | +++++++ |
| |
| warning: unused comparison that must be used |
| --> $DIR/fn_must_use.rs:77:5 |
| | |
| LL | m == n; |
| | ^^^^^^ the comparison produces a value |
| | |
| help: use `let _ = ...` to ignore the resulting value |
| | |
| LL | let _ = m == n; |
| | +++++++ |
| |
| warning: 9 warnings emitted |
| |