diff --git a/compiler/rustc_mir_build/src/build/scope.rs b/compiler/rustc_mir_build/src/build/scope.rs index e352db2585f..c2af064925c 100644 --- a/compiler/rustc_mir_build/src/build/scope.rs +++ b/compiler/rustc_mir_build/src/build/scope.rs @@ -1484,14 +1484,6 @@ fn build_scope_drops<'tcx>( block = next; } DropKind::ForLint => { - // If the operand has been moved, and we are not on an unwind - // path, then don't generate the drop. (We only take this into - // account for non-unwind paths so as not to disturb the - // caching mechanism.) - if scope.moved_locals.iter().any(|&o| o == local) { - continue; - } - // As in the `DropKind::Storage` case below: // normally lint-related drops are not emitted for unwind, // so we can just leave `unwind_to` unmodified, but in some @@ -1503,6 +1495,14 @@ fn build_scope_drops<'tcx>( unwind_to = unwind_drops.drops[unwind_to].next; } + // If the operand has been moved, and we are not on an unwind + // path, then don't generate the drop. (We only take this into + // account for non-unwind paths so as not to disturb the + // caching mechanism.) + if scope.moved_locals.iter().any(|&o| o == local) { + continue; + } + cfg.push(block, Statement { source_info, kind: StatementKind::BackwardIncompatibleDropHint { @@ -1555,7 +1555,7 @@ impl<'a, 'tcx: 'a> Builder<'a, 'tcx> { let mut unwind_indices = IndexVec::from_elem_n(unwind_target, 1); for (drop_idx, drop_node) in drops.drops.iter_enumerated().skip(1) { match drop_node.data.kind { - DropKind::Storage => { + DropKind::Storage | DropKind::ForLint => { if is_coroutine { let unwind_drop = self .scopes @@ -1566,7 +1566,7 @@ impl<'a, 'tcx: 'a> Builder<'a, 'tcx> { unwind_indices.push(unwind_indices[drop_node.next]); } } - DropKind::Value | DropKind::ForLint => { + DropKind::Value => { let unwind_drop = self .scopes .unwind_drops diff --git a/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.rs b/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.rs new file mode 100644 index 00000000000..8d85cee19fd --- /dev/null +++ b/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.rs @@ -0,0 +1,29 @@ +//@ edition: 2021 +//@ build-fail + +// Make sure we don't ICE when emitting the "lint" drop statement +// used for tail_expr_drop_order. + +#![deny(tail_expr_drop_order)] + +struct Drop; +impl std::ops::Drop for Drop { + fn drop(&mut self) {} +} + +async fn func() -> Result<(), Drop> { + todo!() +} + +async fn retry_db() -> Result<(), Drop> { + loop { + match func().await { + //~^ ERROR relative drop order changing in Rust 2024 + //~| WARNING this changes meaning in Rust 2024 + Ok(()) => return Ok(()), + Err(e) => {} + } + } +} + +fn main() {} diff --git a/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.stderr b/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.stderr new file mode 100644 index 00000000000..37220c40b8b --- /dev/null +++ b/tests/ui/drop/tail_expr_drop_order-on-coroutine-unwind.stderr @@ -0,0 +1,52 @@ +error: relative drop order changing in Rust 2024 + --> $DIR/tail_expr_drop_order-on-coroutine-unwind.rs:20:15 + | +LL | match func().await { + | ^^^^^^^----- + | | | + | | this value will be stored in a temporary; let us call it `#1` + | | `#1` will be dropped later as of Edition 2024 + | this value will be stored in a temporary; let us call it `#2` + | up until Edition 2021 `#2` is dropped last but will be dropped earlier in Edition 2024 +... +LL | Err(e) => {} + | - + | | + | `e` calls a custom destructor + | `e` will be dropped later as of Edition 2024 +LL | } +LL | } + | - now the temporary value is dropped here, before the local variables in the block or statement + | + = warning: this changes meaning in Rust 2024 + = note: for more information, see issue #123739 +note: `#2` invokes this custom destructor + --> $DIR/tail_expr_drop_order-on-coroutine-unwind.rs:10:1 + | +LL | / impl std::ops::Drop for Drop { +LL | | fn drop(&mut self) {} +LL | | } + | |_^ +note: `#1` invokes this custom destructor + --> $DIR/tail_expr_drop_order-on-coroutine-unwind.rs:10:1 + | +LL | / impl std::ops::Drop for Drop { +LL | | fn drop(&mut self) {} +LL | | } + | |_^ +note: `e` invokes this custom destructor + --> $DIR/tail_expr_drop_order-on-coroutine-unwind.rs:10:1 + | +LL | / impl std::ops::Drop for Drop { +LL | | fn drop(&mut self) {} +LL | | } + | |_^ + = note: most of the time, changing drop order is harmless; inspect the `impl Drop`s for side effects like releasing locks or sending messages +note: the lint level is defined here + --> $DIR/tail_expr_drop_order-on-coroutine-unwind.rs:7:9 + | +LL | #![deny(tail_expr_drop_order)] + | ^^^^^^^^^^^^^^^^^^^^ + +error: aborting due to 1 previous error +