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Don't refer to 'this tail expression' in expansion. #142024

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Merged
merged 1 commit into from
Jun 5, 2025
Merged

Don't refer to 'this tail expression' in expansion. #142024

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4 changes: 3 additions & 1 deletion compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -3841,7 +3841,9 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
.expr_ty_adjusted_opt(inner_expr)
.unwrap_or(Ty::new_misc_error(tcx));
let span = inner_expr.span;
if Some(span) != err.span.primary_span() {
if Some(span) != err.span.primary_span()
&& !span.in_external_macro(tcx.sess.source_map())
{
err.span_label(
span,
if ty.references_error() {
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6 changes: 2 additions & 4 deletions tests/ui/never_type/feature-gate-never_type_fallback.stderr
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Expand Up @@ -2,10 +2,8 @@ error[E0277]: the trait bound `(): T` is not satisfied
--> $DIR/feature-gate-never_type_fallback.rs:10:9
|
LL | foo(panic!())
| --- ^^^^^^^^
| | |
| | the trait `T` is not implemented for `()`
| | this tail expression is of type `()`
Comment on lines -5 to -8
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Remark: what's slightly amusing is that the Reference calls the tail expr of an block expr the "final operand"

The syntax for a block is [...] then an optional expression, called the final operand, and finally a }.
-- https://doc.rust-lang.org/reference/expressions/block-expr.html#r-expr.block.inner-attributes

| --- ^^^^^^^^ the trait `T` is not implemented for `()`
| |
| required by a bound introduced by this call
|
help: this trait has no implementations, consider adding one
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