Fixes according comments in PR

crates/lang/codegen/src/generator/trait_def/trait_registry.rs

@@ -106,7 +106,7 @@ impl TraitRegistry<'_> {
             /// # Note
             ///
             /// That implementation is used by builder generated in the body of the contract
-            /// and by reference to contract(aka `ContractRef` in case of `Contract`).
+            /// and by reference to contract (a.k.a `ContractRef` in case of `Contract`).
             impl<T> #trait_ident for T
             where
                 T: ::ink_lang::reflect::CallBuilder,

crates/lang/src/reflect/trait_def/info.rs

@@ -158,4 +158,10 @@ pub trait TraitModulePath {
     const NAME: &'static str;
 }
 
+/// Implemented by call builders of smart contracts and by `TraitDefinitionRegistry`
+/// during codegen to apply the blanket implementation.
+///
+/// The blanket implementation is generated by `#[ink_lang::trait_definition]` and
+/// defined in the same place with the trait. It generates the body for methods of the trait.
+/// These methods contain cross-contract calls inside and define the `__ink_TraitInfo`.
 pub trait CallBuilder: ContractEnv + ToAccountId<<Self as ContractEnv>::Env> {}

crates/lang/src/reflect/trait_def/registry.rs

@@ -72,14 +72,21 @@ impl<E> ToAccountId<E> for TraitDefinitionRegistry<E>
 where
     E: ink_env::Environment,
 {
+    /// `to_account_id` is not allowed for `TraitDefinitionRegistry`.
+    ///
+    /// We insert markers for these errors in the generated contract code.
+    /// This is necessary since we can't check these errors at compile time
+    /// of the contract.
+    /// `cargo-contract` checks the contract code for these error markers
+    /// when building a contract and fails if it finds markers.
     #[cold]
     fn to_account_id(&self) -> E::AccountId {
         /// We enforce linking errors in case this is ever actually called.
         /// These linker errors are properly resolved by the cargo-contract tool.
         extern "C" {
-            fn _ink_compilation_error() -> !;
+            fn __ink_enforce_error_to_account_id() -> !;
         }
-        unsafe { _ink_compilation_error() }
+        unsafe { __ink_enforce_error_to_account_id() }
     }
 }