diff options
| -rw-r--r-- | src/librustc_mir/build/expr/stmt.rs | 18 | ||||
| -rw-r--r-- | src/test/ui/nll/issue-54382-use-span-of-tail-of-block.nll.stderr | 2 |
2 files changed, 19 insertions, 1 deletions
diff --git a/src/librustc_mir/build/expr/stmt.rs b/src/librustc_mir/build/expr/stmt.rs index 708ddd3842d..45235b31539 100644 --- a/src/librustc_mir/build/expr/stmt.rs +++ b/src/librustc_mir/build/expr/stmt.rs @@ -210,6 +210,7 @@ impl<'a, 'gcx, 'tcx> Builder<'a, 'gcx, 'tcx> { // it is usually better to focus on `the_value` rather // than the entirety of block(s) surrounding it. let mut temp_span = expr_span; + let mut temp_in_tail_of_block = false; if let ExprKind::Block { body } = expr.kind { if let Some(tail_expr) = &body.expr { let mut expr = tail_expr; @@ -221,10 +222,25 @@ impl<'a, 'gcx, 'tcx> Builder<'a, 'gcx, 'tcx> { } } temp_span = expr.span; + temp_in_tail_of_block = true; } } - let temp = this.temp(expr.ty.clone(), temp_span); + let temp = { + let mut local_decl = LocalDecl::new_temp(expr.ty.clone(), temp_span); + if temp_in_tail_of_block { + if this.block_context.currently_ignores_tail_results() { + local_decl = local_decl.block_tail(BlockTailInfo { + tail_result_is_ignored: true + }); + } + } + let temp = this.local_decls.push(local_decl); + let place = Place::Local(temp); + debug!("created temp {:?} for expr {:?} in block_context: {:?}", + temp, expr, this.block_context); + place + }; unpack!(block = this.into(&temp, block, expr)); // Attribute drops of the statement's temps to the diff --git a/src/test/ui/nll/issue-54382-use-span-of-tail-of-block.nll.stderr b/src/test/ui/nll/issue-54382-use-span-of-tail-of-block.nll.stderr index 31f49b2836e..c308562c0cc 100644 --- a/src/test/ui/nll/issue-54382-use-span-of-tail-of-block.nll.stderr +++ b/src/test/ui/nll/issue-54382-use-span-of-tail-of-block.nll.stderr @@ -12,6 +12,8 @@ LL | } LL | LL | ; | - ... and the borrow might be used here, when that temporary is dropped and runs the `Drop` code for type `D` + | + = note: The temporary is part of an expression at the end of a block. Consider adding semicolon after the expression so its temporaries are dropped sooner, before the local variables declared by the block are dropped. error: aborting due to previous error |