diff options
| -rw-r--r-- | compiler/rustc_hir_typeck/src/cast.rs | 1 | ||||
| -rw-r--r-- | tests/ui/closures/closure-no-fn-3.stderr | 6 |
2 files changed, 7 insertions, 0 deletions
diff --git a/compiler/rustc_hir_typeck/src/cast.rs b/compiler/rustc_hir_typeck/src/cast.rs index 341d533492d..65229722771 100644 --- a/compiler/rustc_hir_typeck/src/cast.rs +++ b/compiler/rustc_hir_typeck/src/cast.rs @@ -495,6 +495,7 @@ impl<'a, 'tcx> CastCheck<'tcx> { err.span_label(self.span, "invalid cast"); } + fcx.suggest_no_capture_closure(&mut err, self.cast_ty, self.expr_ty); self.try_suggest_collection_to_bool(fcx, &mut err); err.emit(); diff --git a/tests/ui/closures/closure-no-fn-3.stderr b/tests/ui/closures/closure-no-fn-3.stderr index bbf3677fb72..7711347c568 100644 --- a/tests/ui/closures/closure-no-fn-3.stderr +++ b/tests/ui/closures/closure-no-fn-3.stderr @@ -3,6 +3,12 @@ error[E0605]: non-primitive cast: `{closure@$DIR/closure-no-fn-3.rs:6:28: 6:30}` | LL | let baz: fn() -> u8 = (|| { b }) as fn() -> u8; | ^^^^^^^^^^^^^^^^^^^^^^^^ invalid cast + | +note: closures can only be coerced to `fn` types if they do not capture any variables + --> $DIR/closure-no-fn-3.rs:6:33 + | +LL | let baz: fn() -> u8 = (|| { b }) as fn() -> u8; + | ^ `b` captured here error: aborting due to 1 previous error |