Make the suggestion message of unused_must_use scarier.

compiler/rustc_lint/src/diagnostics.rs

@@ -2613,7 +2613,7 @@ pub(crate) struct UnusedOp<'a> {
 #[derive(Subdiagnostic)]
 pub(crate) enum UnusedOpSuggestion {
     #[suggestion(
-        "use `let _ = ...` to ignore the resulting value",
+        "if you wish to disregard this recommendation, use `let _ = ...` to ignore the value",
         style = "verbose",
         code = "let _ = ",
         applicability = "maybe-incorrect"
@@ -2623,7 +2623,7 @@ pub(crate) enum UnusedOpSuggestion {
         span: Span,
     },
     #[multipart_suggestion(
-        "use `let _ = ...` to ignore the resulting value",
+        "if you wish to disregard this recommendation, use `let _ = ...` to ignore the value",
         style = "verbose",
         applicability = "maybe-incorrect"
     )]
@@ -2687,7 +2687,7 @@ pub(crate) struct UnusedDef<'a, 'b> {
 #[derive(Subdiagnostic)]
 pub(crate) enum UnusedDefSuggestion {
     #[suggestion(
-        "use `let _ = ...` to ignore the resulting value",
+        "if you wish to disregard this recommendation, use `let _ = ...` to ignore the value",
         style = "verbose",
         code = "let _ = ",
         applicability = "maybe-incorrect"
@@ -2697,7 +2697,7 @@ pub(crate) enum UnusedDefSuggestion {
         span: Span,
     },
     #[multipart_suggestion(
-        "use `let _ = ...` to ignore the resulting value",
+        "if you wish to disregard this recommendation, use `let _ = ...` to ignore the value",
         style = "verbose",
         applicability = "maybe-incorrect"
     )]
@@ -2708,7 +2708,7 @@ pub(crate) enum UnusedDefSuggestion {
         after_span: Span,
     },
     #[suggestion(
-        "use `let _unused = ...` to ignore the resulting value without dropping it immediately",
+        "if you wish to disregard this recommendation, use `let _unused = ...` to ignore the resulting value without dropping it immediately",
         style = "verbose",
         code = "let _unused = ",
         applicability = "maybe-incorrect"
@@ -2718,7 +2718,7 @@ pub(crate) enum UnusedDefSuggestion {
         span: Span,
     },
     #[multipart_suggestion(
-        "use `let _unused = ...` to ignore the resulting value without dropping it immediately",
+        "if you wish to disregard this recommendation, use `let _unused = ...` to ignore the resulting value without dropping it immediately",
         style = "verbose",
         applicability = "maybe-incorrect"
     )]

tests/ui/attributes/attr-order-must-use.stderr

@@ -25,7 +25,7 @@ LL |     must_use();
    |
    = note: AAA
    = note: `#[deny(unused_must_use)]` implied by `#[deny(unused)]`
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = must_use();
    |     +++++++

tests/ui/conditional-compilation/cfg-attr-multi-true.stderr

@@ -35,7 +35,7 @@ note: the lint level is defined here
    |
 LL | #![warn(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = MustUseDeprecated::new();
    |     +++++++

tests/ui/lint/decorate-ice/decorate-can-emit-warnings.stderr

@@ -5,7 +5,7 @@ LL |     f();
    |     ^^^
    |
    = note: requested on the command line with `-D unused-must-use`
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = f();
    |     +++++++

tests/ui/lint/decorate-ice/decorate-force-warn.stderr

@@ -5,7 +5,7 @@ LL |     f();
    |     ^^^
    |
    = note: requested on the command line with `--force-warn unused-must-use`
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = f();
    |     +++++++

tests/ui/lint/fn_must_use.stderr

@@ -20,7 +20,7 @@ note: the lint level is defined here
    |
 LL | #![warn(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = need_to_use_this_value();
    |     +++++++
@@ -31,7 +31,7 @@ warning: unused return value of `MyStruct::need_to_use_this_method_value` that m
 LL |     m.need_to_use_this_method_value();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = m.need_to_use_this_method_value();
    |     +++++++
@@ -43,7 +43,7 @@ LL |     m.is_even(); // trait method!
    |     ^^^^^^^^^^^
    |
    = note: no side effects
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = m.is_even(); // trait method!
    |     +++++++
@@ -54,7 +54,7 @@ warning: unused return value of `MyStruct::need_to_use_this_associated_function_
 LL |     MyStruct::need_to_use_this_associated_function_value();
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = MyStruct::need_to_use_this_associated_function_value();
    |     +++++++
@@ -65,7 +65,7 @@ warning: unused return value of `std::cmp::PartialEq::eq` that must be used
 LL |     2.eq(&3);
    |     ^^^^^^^^
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = 2.eq(&3);
    |     +++++++
@@ -76,7 +76,7 @@ warning: unused return value of `std::cmp::PartialEq::eq` that must be used
 LL |     m.eq(&n);
    |     ^^^^^^^^
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = m.eq(&n);
    |     +++++++
@@ -87,7 +87,7 @@ warning: unused comparison that must be used
 LL |     2 == 3;
    |     ^^^^^^ the comparison produces a value
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = 2 == 3;
    |     +++++++
@@ -98,7 +98,7 @@ warning: unused comparison that must be used
 LL |     m == n;
    |     ^^^^^^ the comparison produces a value
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = m == n;
    |     +++++++

tests/ui/lint/unused-borrows.stderr

@@ -9,7 +9,7 @@ note: the lint level is defined here
    |
 LL | #![deny(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = &42;
    |     +++++++
@@ -20,7 +20,7 @@ error: unused borrow that must be used
 LL |     &mut foo(42);
    |     ^^^^^^^^^^^^ the borrow produces a value
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = &mut foo(42);
    |     +++++++
@@ -31,7 +31,7 @@ error: unused borrow that must be used
 LL |     &&42;
    |     ^^^^ the borrow produces a value
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = &&42;
    |     +++++++
@@ -42,7 +42,7 @@ error: unused borrow that must be used
 LL |     &&mut 42;
    |     ^^^^^^^^ the borrow produces a value
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = &&mut 42;
    |     +++++++
@@ -53,7 +53,7 @@ error: unused borrow that must be used
 LL |     &mut &42;
    |     ^^^^^^^^ the borrow produces a value
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = &mut &42;
    |     +++++++
@@ -64,7 +64,7 @@ error: unused borrow that must be used
 LL |     && foo(42);
    |     ^^^^^^^^^^ the borrow produces a value
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = && foo(42);
    |     +++++++

tests/ui/lint/unused/issue-103320-must-use-ops.stderr

@@ -10,7 +10,7 @@ note: the lint level is defined here
    |
 LL | #![warn(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = x.add(4);
    |     +++++++
@@ -22,7 +22,7 @@ LL |     x.sub(4);
    |     ^^^^^^^^
    |
    = note: this returns the result of the operation, without modifying the original
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = x.sub(4);
    |     +++++++
@@ -34,7 +34,7 @@ LL |     x.mul(4);
    |     ^^^^^^^^
    |
    = note: this returns the result of the operation, without modifying the original
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = x.mul(4);
    |     +++++++
@@ -46,7 +46,7 @@ LL |     x.div(4);
    |     ^^^^^^^^
    |
    = note: this returns the result of the operation, without modifying the original
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = x.div(4);
    |     +++++++
@@ -58,7 +58,7 @@ LL |     x.rem(4);
    |     ^^^^^^^^
    |
    = note: this returns the result of the operation, without modifying the original
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = x.rem(4);
    |     +++++++

tests/ui/lint/unused/issue-85913.stderr

@@ -9,7 +9,7 @@ note: the lint level is defined here
    |
 LL | #![deny(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = function() && return 1;
    |     +++++++

tests/ui/lint/unused/lint-unsed-in-macro-issue-151269.stderr

@@ -10,7 +10,7 @@ note: the lint level is defined here
    |
 LL | #![deny(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |         let _ = error();
    |         +++++++

tests/ui/lint/unused/must-use-block-expr.stderr

@@ -9,7 +9,7 @@ note: the lint level is defined here
    |
 LL | #![warn(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |         let _ = foo();
    |         +++++++
@@ -20,7 +20,7 @@ warning: unused return value of `foo` that must be used
 LL |         foo()
    |         ^^^^^
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |         let _ = foo();
    |         +++++++      +
@@ -31,7 +31,7 @@ warning: unused arithmetic operation that must be used
 LL |         1 + 2;
    |         ^^^^^ the arithmetic operation produces a value
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |         let _ = 1 + 2;
    |         +++++++
@@ -42,7 +42,7 @@ warning: unused arithmetic operation that must be used
 LL |         1 + 2
    |         ^^^^^ the arithmetic operation produces a value
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |         let _ = 1 + 2;
    |         +++++++      +

tests/ui/lint/unused/must-use-box-from-raw.stderr

@@ -10,7 +10,7 @@ note: the lint level is defined here
    |
 LL | #![warn(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-help: use `let _unused = ...` to ignore the resulting value without dropping it immediately
+help: if you wish to disregard this recommendation, use `let _unused = ...` to ignore the resulting value without dropping it immediately
    |
 LL |     let _unused = Box::from_raw(ptr);
    |     +++++++++++++

tests/ui/lint/unused/must-use-lock-guard-issue-162843.stderr

@@ -10,7 +10,7 @@ note: the lint level is defined here
    |
 LL | #![deny(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-help: use `let _unused = ...` to ignore the resulting value without dropping it immediately
+help: if you wish to disregard this recommendation, use `let _unused = ...` to ignore the resulting value without dropping it immediately
    |
 LL |     let _unused = mutex.lock().unwrap();
    |     +++++++++++++
@@ -21,7 +21,7 @@ error: unused return value of `guard` that must be used
 LL |     guard();
    |     ^^^^^^^
    |
-help: use `let _unused = ...` to ignore the resulting value without dropping it immediately
+help: if you wish to disregard this recommendation, use `let _unused = ...` to ignore the resulting value without dropping it immediately
    |
 LL |     let _unused = guard();
    |     +++++++++++++
@@ -32,7 +32,7 @@ error: unused return value of `value` that must be used
 LL |     value();
    |     ^^^^^^^
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = value();
    |     +++++++
@@ -43,7 +43,7 @@ error: unused return value of `vec_values` that must be used
 LL |     vec_values();
    |     ^^^^^^^^^^^^
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = vec_values();
    |     +++++++
@@ -54,7 +54,7 @@ error: unused return value of `box_value` that must be used
 LL |     box_value();
    |     ^^^^^^^^^^^
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |     let _ = box_value();
    |     +++++++

tests/ui/lint/unused/must-use-macros.stderr

@@ -14,7 +14,7 @@ note: the lint level is defined here
    |
 LL | #![warn(unused_must_use)]
    |         ^^^^^^^^^^^^^^^
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |         let _ = cmp!(a, b);
    |         +++++++
@@ -30,7 +30,7 @@ LL |                 $a == $b
 LL |         cmp!(1, 1);
    |         ---------- in this macro invocation
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |         let _ = cmp!(1, 1);
    |         +++++++
@@ -41,7 +41,7 @@ warning: unused return value of `std::cmp::PartialEq::eq` that must be used
 LL |         cmp!(1, 1);
    |         ^^^^^^^^^^
    |
-help: use `let _ = ...` to ignore the resulting value
+help: if you wish to disregard this recommendation, use `let _ = ...` to ignore the value
    |
 LL |         let _ = cmp!(1, 1);
    |         +++++++