Auto merge of #36840 - eulerdisk:incr_test_for_hash_enum, r=michaelwoerister

Test Case for Incr. Comp. Hash for enums #36674.

Fixes #36674
Part of #36350

r? @michaelwoerister

src/test/incremental/hashes/enum_defs.rs

@@ -0,0 +1,715 @@
+// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+
+// This test case tests the incremental compilation hash (ICH) implementation
+// for enum definitions.
+
+// The general pattern followed here is: Change one thing between rev1 and rev2
+// and make sure that the hash has changed, then change nothing between rev2 and
+// rev3 and make sure that the hash has not changed.
+
+// We also test the ICH for enum definitions exported in metadata. Same as
+// above, we want to make sure that the change between rev1 and rev2 also
+// results in a change of the ICH for the enum's metadata, and that it stays
+// the same between rev2 and rev3.
+
+// must-compile-successfully
+// revisions: cfail1 cfail2 cfail3
+// compile-flags: -Z query-dep-graph
+
+#![allow(warnings)]
+#![feature(rustc_attrs)]
+#![crate_type="rlib"]
+
+
+
+// Change enum visibility -----------------------------------------------------
+#[cfg(cfail1)]
+enum EnumVisibility { A }
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_clean(cfg="cfail3")]
+pub enum EnumVisibility { A }
+
+
+
+// Change name of a c-style variant -------------------------------------------
+#[cfg(cfail1)]
+enum EnumChangeNameCStyleVariant {
+    Variant1,
+    Variant2,
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumChangeNameCStyleVariant {
+    Variant1,
+    Variant2Changed,
+}
+
+
+
+// Change name of a tuple-style variant ---------------------------------------
+#[cfg(cfail1)]
+enum EnumChangeNameTupleStyleVariant {
+    Variant1,
+    Variant2(u32, f32),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumChangeNameTupleStyleVariant {
+    Variant1,
+    Variant2Changed(u32, f32),
+}
+
+
+
+// Change name of a struct-style variant --------------------------------------
+#[cfg(cfail1)]
+enum EnumChangeNameStructStyleVariant {
+    Variant1,
+    Variant2 { a: u32, b: f32 },
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumChangeNameStructStyleVariant {
+    Variant1,
+    Variant2Changed { a: u32, b: f32 },
+}
+
+
+
+// Change the value of a c-style variant --------------------------------------
+#[cfg(cfail1)]
+enum EnumChangeValueCStyleVariant0 {
+    Variant1,
+    Variant2 = 11,
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumChangeValueCStyleVariant0 {
+    Variant1,
+    Variant2 = 22,
+}
+
+#[cfg(cfail1)]
+enum EnumChangeValueCStyleVariant1 {
+    Variant1,
+    Variant2,
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumChangeValueCStyleVariant1 {
+    Variant1,
+    Variant2 = 11,
+}
+
+
+
+// Add a c-style variant ------------------------------------------------------
+#[cfg(cfail1)]
+enum EnumAddCStyleVariant {
+    Variant1,
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumAddCStyleVariant {
+    Variant1,
+    Variant2,
+}
+
+
+
+// Remove a c-style variant ---------------------------------------------------
+#[cfg(cfail1)]
+enum EnumRemoveCStyleVariant {
+    Variant1,
+    Variant2,
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumRemoveCStyleVariant {
+    Variant1,
+}
+
+
+
+// Add a tuple-style variant --------------------------------------------------
+#[cfg(cfail1)]
+enum EnumAddTupleStyleVariant {
+    Variant1,
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumAddTupleStyleVariant {
+    Variant1,
+    Variant2(u32, f32),
+}
+
+
+
+// Remove a tuple-style variant -----------------------------------------------
+#[cfg(cfail1)]
+enum EnumRemoveTupleStyleVariant {
+    Variant1,
+    Variant2(u32, f32),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumRemoveTupleStyleVariant {
+    Variant1,
+}
+
+
+
+// Add a struct-style variant -------------------------------------------------
+#[cfg(cfail1)]
+enum EnumAddStructStyleVariant {
+    Variant1,
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumAddStructStyleVariant {
+    Variant1,
+    Variant2 { a: u32, b: f32 },
+}
+
+
+
+// Remove a struct-style variant ----------------------------------------------
+#[cfg(cfail1)]
+enum EnumRemoveStructStyleVariant {
+    Variant1,
+    Variant2 { a: u32, b: f32 },
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumRemoveStructStyleVariant {
+    Variant1,
+}
+
+
+
+// Change the type of a field in a tuple-style variant ------------------------
+#[cfg(cfail1)]
+enum EnumChangeFieldTypeTupleStyleVariant {
+    Variant1(u32, u32),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumChangeFieldTypeTupleStyleVariant {
+    Variant1(u32, u64),
+}
+
+
+
+// Change the type of a field in a struct-style variant -----------------------
+#[cfg(cfail1)]
+enum EnumChangeFieldTypeStructStyleVariant {
+    Variant1,
+    Variant2 { a: u32, b: u32 },
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumChangeFieldTypeStructStyleVariant {
+    Variant1,
+    Variant2 { a: u32, b: u64 },
+}
+
+
+
+// Change the name of a field in a struct-style variant -----------------------
+#[cfg(cfail1)]
+enum EnumChangeFieldNameStructStyleVariant {
+    Variant1 { a: u32, b: u32 },
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumChangeFieldNameStructStyleVariant {
+    Variant1 { a: u32, c: u32 },
+}
+
+
+
+// Change order of fields in a tuple-style variant ----------------------------
+#[cfg(cfail1)]
+enum EnumChangeOrderTupleStyleVariant {
+    Variant1(u32, u64),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumChangeOrderTupleStyleVariant {
+    Variant1(u64, u32),
+}
+
+
+
+// Change order of fields in a struct-style variant ---------------------------
+#[cfg(cfail1)]
+enum EnumChangeFieldOrderStructStyleVariant {
+    Variant1 { a: u32, b: f32 },
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumChangeFieldOrderStructStyleVariant {
+    Variant1 { b: f32, a: u32 },
+}
+
+
+
+// Add a field to a tuple-style variant ---------------------------------------
+#[cfg(cfail1)]
+enum EnumAddFieldTupleStyleVariant {
+    Variant1(u32, u32),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumAddFieldTupleStyleVariant {
+    Variant1(u32, u32, u32),
+}
+
+
+
+// Add a field to a struct-style variant --------------------------------------
+#[cfg(cfail1)]
+enum EnumAddFieldStructStyleVariant {
+    Variant1 { a: u32, b: u32 },
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumAddFieldStructStyleVariant {
+    Variant1 { a: u32, b: u32, c: u32 },
+}
+
+
+
+// Add #[must_use] to the enum ------------------------------------------------
+#[cfg(cfail1)]
+enum EnumAddMustUse {
+    Variant1,
+    Variant2,
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[must_use]
+enum EnumAddMustUse {
+    Variant1,
+    Variant2,
+}
+
+
+
+// Add #[repr(C)] to the enum -------------------------------------------------
+#[cfg(cfail1)]
+enum EnumAddReprC {
+    Variant1,
+    Variant2,
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumAddReprC {
+    Variant1,
+    Variant2,
+}
+
+
+
+// Change the name of a type parameter ----------------------------------------
+#[cfg(cfail1)]
+enum EnumChangeNameOfTypeParameter<S> {
+    Variant1(S),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumChangeNameOfTypeParameter<T> {
+    Variant1(T),
+}
+
+
+
+// Add a type parameter ------------------------------------------------------
+#[cfg(cfail1)]
+enum EnumAddTypeParameter<S> {
+    Variant1(S),
+    Variant2(S),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumAddTypeParameter<S, T> {
+    Variant1(S),
+    Variant2(T),
+}
+
+
+
+// Change the name of a lifetime parameter ------------------------------------
+#[cfg(cfail1)]
+enum EnumChangeNameOfLifetimeParameter<'a> {
+    Variant1(&'a u32),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumChangeNameOfLifetimeParameter<'b> {
+    Variant1(&'b u32),
+}
+
+
+
+// Add a lifetime parameter ---------------------------------------------------
+#[cfg(cfail1)]
+enum EnumAddLifetimeParameter<'a> {
+    Variant1(&'a u32),
+    Variant2(&'a u32),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumAddLifetimeParameter<'a, 'b> {
+    Variant1(&'a u32),
+    Variant2(&'b u32),
+}
+
+
+
+// Add a lifetime bound to a lifetime parameter -------------------------------
+#[cfg(cfail1)]
+enum EnumAddLifetimeParameterBound<'a, 'b> {
+    Variant1(&'a u32),
+    Variant2(&'b u32),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumAddLifetimeParameterBound<'a, 'b: 'a> {
+    Variant1(&'a u32),
+    Variant2(&'b u32),
+}
+
+// Add a lifetime bound to a type parameter -----------------------------------
+#[cfg(cfail1)]
+enum EnumAddLifetimeBoundToParameter<'a, T> {
+    Variant1(T),
+    Variant2(&'a u32),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumAddLifetimeBoundToParameter<'a, T: 'a> {
+    Variant1(T),
+    Variant2(&'a u32),
+}
+
+
+
+// Add a trait bound to a type parameter --------------------------------------
+#[cfg(cfail1)]
+enum EnumAddTraitBound<S> {
+    Variant1(S),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumAddTraitBound<T: Sync> {
+    Variant1(T),
+}
+
+
+
+// Add a lifetime bound to a lifetime parameter in where clause ---------------
+#[cfg(cfail1)]
+enum EnumAddLifetimeParameterBoundWhere<'a, 'b> {
+    Variant1(&'a u32),
+    Variant2(&'b u32),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumAddLifetimeParameterBoundWhere<'a, 'b> where 'b: 'a {
+    Variant1(&'a u32),
+    Variant2(&'b u32),
+}
+
+
+
+// Add a lifetime bound to a type parameter in where clause -------------------
+#[cfg(cfail1)]
+enum EnumAddLifetimeBoundToParameterWhere<'a, T> {
+    Variant1(T),
+    Variant2(&'a u32),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumAddLifetimeBoundToParameterWhere<'a, T> where T: 'a {
+    Variant1(T),
+    Variant2(&'a u32),
+}
+
+
+
+// Add a trait bound to a type parameter in where clause ----------------------
+#[cfg(cfail1)]
+enum EnumAddTraitBoundWhere<S> {
+    Variant1(S),
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+#[repr(C)]
+enum EnumAddTraitBoundWhere<T> where T: Sync {
+    Variant1(T),
+}
+
+
+
+// In an enum with two variants, swap usage of type parameters ----------------
+#[cfg(cfail1)]
+enum EnumSwapUsageTypeParameters<A, B> {
+    Variant1 { a: A },
+    Variant2 { a: B },
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumSwapUsageTypeParameters<A, B> {
+    Variant1 { a: B },
+    Variant2 { a: A },
+}
+
+
+
+// In an enum with two variants, swap usage of lifetime parameters ------------
+#[cfg(cfail1)]
+enum EnumSwapUsageLifetimeParameters<'a, 'b> {
+    Variant1 { a: &'a u32 },
+    Variant2 { b: &'b u32 },
+}
+
+#[cfg(not(cfail1))]
+#[rustc_dirty(label="Hir", cfg="cfail2")]
+#[rustc_clean(label="Hir", cfg="cfail3")]
+#[rustc_metadata_dirty(cfg="cfail2")]
+#[rustc_metadata_clean(cfg="cfail3")]
+enum EnumSwapUsageLifetimeParameters<'a, 'b> {
+    Variant1 { a: &'b u32 },
+    Variant2 { b: &'a u32 },
+}
+
+
+
+struct ReferencedType1;
+struct ReferencedType2;
+
+
+
+// Change field type in tuple-style variant indirectly by modifying a use statement
+mod change_field_type_indirectly_tuple_style {
+    #[cfg(cfail1)]
+    use super::ReferencedType1 as FieldType;
+    #[cfg(not(cfail1))]
+    use super::ReferencedType2 as FieldType;
+
+    #[rustc_dirty(label="Hir", cfg="cfail2")]
+    #[rustc_clean(label="Hir", cfg="cfail3")]
+    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    enum TupleStyle {
+        Variant1(FieldType)
+    }
+}
+
+
+
+// Change field type in record-style variant indirectly by modifying a use statement
+mod change_field_type_indirectly_struct_style {
+    #[cfg(cfail1)]
+    use super::ReferencedType1 as FieldType;
+    #[cfg(not(cfail1))]
+    use super::ReferencedType2 as FieldType;
+
+    #[rustc_dirty(label="Hir", cfg="cfail2")]
+    #[rustc_clean(label="Hir", cfg="cfail3")]
+    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    enum StructStyle {
+        Variant1 { a: FieldType }
+    }
+}
+
+
+
+trait ReferencedTrait1 {}
+trait ReferencedTrait2 {}
+
+
+
+// Change trait bound of type parameter indirectly by modifying a use statement
+mod change_trait_bound_indirectly {
+    #[cfg(cfail1)]
+    use super::ReferencedTrait1 as Trait;
+    #[cfg(not(cfail1))]
+    use super::ReferencedTrait2 as Trait;
+
+    #[rustc_dirty(label="Hir", cfg="cfail2")]
+    #[rustc_clean(label="Hir", cfg="cfail3")]
+    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    enum Enum<T: Trait> {
+        Variant1(T)
+    }
+}
+
+
+
+// Change trait bound of type parameter in where clause indirectly by modifying a use statement
+mod change_trait_bound_indirectly_where {
+    #[cfg(cfail1)]
+    use super::ReferencedTrait1 as Trait;
+    #[cfg(not(cfail1))]
+    use super::ReferencedTrait2 as Trait;
+
+    #[rustc_dirty(label="Hir", cfg="cfail2")]
+    #[rustc_clean(label="Hir", cfg="cfail3")]
+    #[rustc_metadata_dirty(cfg="cfail2")]
+    #[rustc_metadata_clean(cfg="cfail3")]
+    enum Enum<T> where T: Trait {
+        Variant1(T)
+    }
+}
+
+