From 2c94102df522aa6c2f69175ad929761cfbe284ac Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Thu, 8 Sep 2022 02:34:22 +0000
Subject: [PATCH] Generator return doesn't need to be a lang item
---
compiler/rustc_hir/src/lang_items.rs | 1 -
compiler/rustc_middle/src/ty/print/pretty.rs | 6 ++++--
compiler/rustc_span/src/symbol.rs | 1 -
library/core/src/ops/generator.rs | 2 +-
4 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/compiler/rustc_hir/src/lang_items.rs b/compiler/rustc_hir/src/lang_items.rs
index bc1ea1c4c73..ea17c1de9b7 100644
--- a/compiler/rustc_hir/src/lang_items.rs
+++ b/compiler/rustc_hir/src/lang_items.rs
@@ -238,7 +238,6 @@ language_item_table! {
Future, sym::future_trait, future_trait, Target::Trait, GenericRequirement::Exact(0);
GeneratorState, sym::generator_state, gen_state, Target::Enum, GenericRequirement::None;
Generator, sym::generator, gen_trait, Target::Trait, GenericRequirement::Minimum(1);
- GeneratorReturn, sym::generator_return, generator_return, Target::AssocTy, GenericRequirement::None;
Unpin, sym::unpin, unpin_trait, Target::Trait, GenericRequirement::None;
Pin, sym::pin, pin_type, Target::Struct, GenericRequirement::None;
diff --git a/compiler/rustc_middle/src/ty/print/pretty.rs b/compiler/rustc_middle/src/ty/print/pretty.rs
index 1ae3063dae4..b46813e08f1 100644
--- a/compiler/rustc_middle/src/ty/print/pretty.rs
+++ b/compiler/rustc_middle/src/ty/print/pretty.rs
@@ -916,8 +916,10 @@ pub trait PrettyPrinter<'tcx>:
// Skip printing `<[generator@] as Generator<_>>::Return` from async blocks,
// unless we can find out what generator return type it comes from.
let term = if let Some(ty) = term.skip_binder().ty()
- && let ty::Projection(ty::ProjectionTy { item_def_id, substs }) = ty.kind()
- && Some(*item_def_id) == tcx.lang_items().generator_return()
+ && let ty::Projection(proj) = ty.kind()
+ && let assoc = tcx.associated_item(proj.item_def_id)
+ && assoc.trait_container(tcx) == tcx.lang_items().gen_trait()
+ && assoc.name == rustc_span::sym::Return
{
if let ty::Generator(_, substs, _) = substs.type_at(0).kind() {
let return_ty = substs.as_generator().return_ty();
diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index 75b1dfc856a..363a2f53e10 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -763,7 +763,6 @@ symbols! {
gen_future,
gen_kill,
generator,
- generator_return,
generator_state,
generators,
generic_arg_infer,
diff --git a/library/core/src/ops/generator.rs b/library/core/src/ops/generator.rs
index b651b7b233e..3ebd6f8cdbd 100644
--- a/library/core/src/ops/generator.rs
+++ b/library/core/src/ops/generator.rs
@@ -83,7 +83,7 @@ pub trait Generator<R = ()> {
/// `return` statement or implicitly as the last expression of a generator
/// literal. For example futures would use this as `Result<T, E>` as it
/// represents a completed future.
- #[lang = "generator_return"]
+ #[cfg_attr(bootstrap, lang = "generator_return")]
type Return;
/// Resumes the execution of this generator.