1 files changed, 9 insertions, 1 deletions
diff --git a/compiler/rustc_lint/src/unused.rs b/compiler/rustc_lint/src/unused.rs
index c431c048ca0..2b580452a60 100644
--- a/compiler/rustc_lint/src/unused.rs
+++ b/compiler/rustc_lint/src/unused.rs
@@ -161,7 +161,15 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults {
 
         if let Some(must_use_op) = must_use_op {
             cx.struct_span_lint(UNUSED_MUST_USE, expr.span, |lint| {
-                lint.build(&format!("unused {} that must be used", must_use_op)).emit()
+                let mut lint = lint.build(&format!("unused {} that must be used", must_use_op));
+                lint.span_label(expr.span, &format!("the {} produces a value", must_use_op));
+                lint.span_suggestion_verbose(
+                    expr.span.shrink_to_lo(),
+                    "use `let _ = ...` to ignore the resulting value",
+                    "let _ = ".to_string(),
+                    Applicability::MachineApplicable,
+                );
+                lint.emit();
             });
             op_warned = true;
         }