introduce CoercePointeeWellformed for coherence checks at typeck stage

1 files changed, 6 insertions, 0 deletions

diff --git a/compiler/rustc_hir/src/lang_items.rs b/compiler/rustc_hir/src/lang_items.rs
index b6689c95c4b..b18e96646b1 100644
--- a/compiler/rustc_hir/src/lang_items.rs
+++ b/compiler/rustc_hir/src/lang_items.rs
@@ -370,6 +370,8 @@ language_item_table! {
 
     PointerLike,             sym::pointer_like,        pointer_like,               Target::Trait,          GenericRequirement::Exact(0);
 
+    CoercePointeeWellformed, sym::coerce_pointee_wellformed, coerce_pointee_wellformed_trait, Target::Trait,     GenericRequirement::Exact(0);
+
     ConstParamTy,            sym::const_param_ty,      const_param_ty_trait,       Target::Trait,          GenericRequirement::Exact(0);
     UnsizedConstParamTy,     sym::unsized_const_param_ty, unsized_const_param_ty_trait, Target::Trait, GenericRequirement::Exact(0);
 
@@ -429,9 +431,13 @@ language_item_table! {
     ContractCheckRequires,     sym::contract_check_requires,      contract_check_requires_fn,      Target::Fn, GenericRequirement::None;
 }
 
+/// The requirement imposed on the generics of a lang item
 pub enum GenericRequirement {
+    /// No restriction on the generics
     None,
+    /// A minimum number of generics that is demanded on a lang item
     Minimum(usize),
+    /// The number of generics must match precisely as stipulated
     Exact(usize),
 }