diff --git a/compiler/rustc_ast_lowering/src/expr.rs b/compiler/rustc_ast_lowering/src/expr.rs index d64f1a05712a9..9442e0f1a1f35 100644 --- a/compiler/rustc_ast_lowering/src/expr.rs +++ b/compiler/rustc_ast_lowering/src/expr.rs @@ -618,9 +618,9 @@ impl<'hir> LoweringContext<'_, 'hir> { /// Desugar `.await` into: /// ```rust /// match ::std::future::IntoFuture::into_future() { - /// mut pinned => loop { + /// mut __awaitee => loop { /// match unsafe { ::std::future::Future::poll( - /// <::std::pin::Pin>::new_unchecked(&mut pinned), + /// <::std::pin::Pin>::new_unchecked(&mut __awaitee), /// ::std::future::get_context(task_context), /// ) } { /// ::std::task::Poll::Ready(result) => break result, @@ -657,21 +657,24 @@ impl<'hir> LoweringContext<'_, 'hir> { let expr = self.lower_expr_mut(expr); let expr_hir_id = expr.hir_id; - let pinned_ident = Ident::with_dummy_span(sym::pinned); - let (pinned_pat, pinned_pat_hid) = - self.pat_ident_binding_mode(span, pinned_ident, hir::BindingAnnotation::Mutable); + // Note that the name of this binding must not be changed to something else because + // debuggers and debugger extensions expect it to be called `__awaitee`. They use + // this name to identify what is being awaited by a suspended async functions. + let awaitee_ident = Ident::with_dummy_span(sym::__awaitee); + let (awaitee_pat, awaitee_pat_hid) = + self.pat_ident_binding_mode(span, awaitee_ident, hir::BindingAnnotation::Mutable); let task_context_ident = Ident::with_dummy_span(sym::_task_context); // unsafe { // ::std::future::Future::poll( - // ::std::pin::Pin::new_unchecked(&mut pinned), + // ::std::pin::Pin::new_unchecked(&mut __awaitee), // ::std::future::get_context(task_context), // ) // } let poll_expr = { - let pinned = self.expr_ident(span, pinned_ident, pinned_pat_hid); - let ref_mut_pinned = self.expr_mut_addr_of(span, pinned); + let awaitee = self.expr_ident(span, awaitee_ident, awaitee_pat_hid); + let ref_mut_awaitee = self.expr_mut_addr_of(span, awaitee); let task_context = if let Some(task_context_hid) = self.task_context { self.expr_ident_mut(span, task_context_ident, task_context_hid) } else { @@ -681,7 +684,7 @@ impl<'hir> LoweringContext<'_, 'hir> { let new_unchecked = self.expr_call_lang_item_fn_mut( span, hir::LangItem::PinNewUnchecked, - arena_vec![self; ref_mut_pinned], + arena_vec![self; ref_mut_awaitee], Some(expr_hir_id), ); let get_context = self.expr_call_lang_item_fn_mut( @@ -782,8 +785,8 @@ impl<'hir> LoweringContext<'_, 'hir> { span: self.lower_span(span), }); - // mut pinned => loop { ... } - let pinned_arm = self.arm(pinned_pat, loop_expr); + // mut __awaitee => loop { ... } + let awaitee_arm = self.arm(awaitee_pat, loop_expr); // `match ::std::future::IntoFuture::into_future() { ... }` let into_future_span = self.mark_span_with_reason( @@ -799,11 +802,11 @@ impl<'hir> LoweringContext<'_, 'hir> { ); // match { - // mut pinned => loop { .. } + // mut __awaitee => loop { .. } // } hir::ExprKind::Match( into_future_expr, - arena_vec![self; pinned_arm], + arena_vec![self; awaitee_arm], hir::MatchSource::AwaitDesugar, ) } diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index 4dd1c3fed6b36..774cf6a19c76d 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -272,6 +272,7 @@ symbols! { __D, __H, __S, + __awaitee, __try_var, _d, _e, @@ -1022,7 +1023,6 @@ symbols! { pattern_parentheses, phantom_data, pin, - pinned, platform_intrinsics, plugin, plugin_registrar, diff --git a/src/test/codegen/async-fn-debug-awaitee-field.rs b/src/test/codegen/async-fn-debug-awaitee-field.rs new file mode 100644 index 0000000000000..efb345fa9f3e5 --- /dev/null +++ b/src/test/codegen/async-fn-debug-awaitee-field.rs @@ -0,0 +1,23 @@ +// This test makes sure that the generator field capturing the awaitee in a `.await` expression +// is called "__awaitee" in debuginfo. This name must not be changed since debuggers and debugger +// extensions rely on the field having this name. + +// ignore-tidy-linelength +// compile-flags: -C debuginfo=2 --edition=2018 + +async fn foo() {} + +async fn async_fn_test() { + foo().await; +} + +// NONMSVC: [[GEN:!.*]] = !DICompositeType(tag: DW_TAG_structure_type, name: "{async_fn_env#0}", +// MSVC: [[GEN:!.*]] = !DICompositeType(tag: DW_TAG_union_type, name: "enum$", +// CHECK: [[SUSPEND_STRUCT:!.*]] = !DICompositeType(tag: DW_TAG_structure_type, name: "Suspend0", scope: [[GEN]], +// CHECK: !DIDerivedType(tag: DW_TAG_member, name: "__awaitee", scope: [[SUSPEND_STRUCT]], {{.*}}, baseType: [[AWAITEE_TYPE:![0-9]*]], +// NONMSVC: [[AWAITEE_TYPE]] = !DICompositeType(tag: DW_TAG_structure_type, name: "GenFuture", +// MSVC: [[AWAITEE_TYPE]] = !DICompositeType(tag: DW_TAG_structure_type, name: "GenFuture >", + +fn main() { + let _fn = async_fn_test(); +}