Place bounds on fields in rustc_macros derives.

Author: cjgillot

compiler/rustc_macros/src/hash_stable.rs

@@ -43,7 +43,7 @@ fn parse_attributes(field: &syn::Field) -> Attributes {
 
 pub fn hash_stable_generic_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream {
     let generic: syn::GenericParam = parse_quote!(__CTX);
-    s.add_bounds(synstructure::AddBounds::Generics);
+    s.add_bounds(synstructure::AddBounds::Fields);
     s.add_impl_generic(generic);
     s.add_where_predicate(parse_quote! { __CTX: crate::HashStableContext });
     let body = s.each(|bi| {
@@ -86,7 +86,7 @@ pub fn hash_stable_generic_derive(mut s: synstructure::Structure<'_>) -> proc_ma
 
 pub fn hash_stable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream {
     let generic: syn::GenericParam = parse_quote!('__ctx);
-    s.add_bounds(synstructure::AddBounds::Generics);
+    s.add_bounds(synstructure::AddBounds::Fields);
     s.add_impl_generic(generic);
     let body = s.each(|bi| {
         let attrs = parse_attributes(bi.ast());

compiler/rustc_macros/src/lib.rs

@@ -120,6 +120,8 @@ decl_derive!([Decodable] => serialize::decodable_derive);
 decl_derive!([Encodable] => serialize::encodable_derive);
 decl_derive!([TyDecodable] => serialize::type_decodable_derive);
 decl_derive!([TyEncodable] => serialize::type_encodable_derive);
+decl_derive!([IrTyDecodable] => serialize::ir_type_decodable_derive);
+decl_derive!([IrTyEncodable] => serialize::ir_type_encodable_derive);
 decl_derive!([MetadataDecodable] => serialize::meta_decodable_derive);
 decl_derive!([MetadataEncodable] => serialize::meta_encodable_derive);
 decl_derive!([TypeFoldable, attributes(type_foldable)] => type_foldable::type_foldable_derive);

compiler/rustc_macros/src/serialize.rs

@@ -3,13 +3,21 @@ use quote::{quote, quote_spanned};
 use syn::parse_quote;
 use syn::spanned::Spanned;
 
+pub fn ir_type_decodable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream {
+    let decoder_ty = quote! { __D };
+    s.add_impl_generic(parse_quote! {#decoder_ty: crate::codec::TyDecoder});
+    s.add_bounds(synstructure::AddBounds::Fields);
+
+    decodable_body(s, decoder_ty)
+}
+
 pub fn type_decodable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream {
     let decoder_ty = quote! { __D };
     if !s.ast().generics.lifetimes().any(|lt| lt.lifetime.ident == "tcx") {
         s.add_impl_generic(parse_quote! { 'tcx });
     }
     s.add_impl_generic(parse_quote! {#decoder_ty: ::rustc_type_ir::codec::TyDecoder<I = ::rustc_middle::ty::TyCtxt<'tcx>>});
-    s.add_bounds(synstructure::AddBounds::Generics);
+    s.add_bounds(synstructure::AddBounds::Fields);
 
     decodable_body(s, decoder_ty)
 }
@@ -20,15 +28,15 @@ pub fn meta_decodable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2:
     }
     s.add_impl_generic(parse_quote! { '__a });
     let decoder_ty = quote! { DecodeContext<'__a, 'tcx> };
-    s.add_bounds(synstructure::AddBounds::Generics);
+    s.add_bounds(synstructure::AddBounds::Fields);
 
     decodable_body(s, decoder_ty)
 }
 
 pub fn decodable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream {
     let decoder_ty = quote! { __D };
     s.add_impl_generic(parse_quote! {#decoder_ty: ::rustc_serialize::Decoder});
-    s.add_bounds(synstructure::AddBounds::Generics);
+    s.add_bounds(synstructure::AddBounds::Fields);
 
     decodable_body(s, decoder_ty)
 }
@@ -90,13 +98,21 @@ fn decode_field(field: &syn::Field) -> proc_macro2::TokenStream {
     quote_spanned! {field_span=> #decode_inner_method(#__decoder) }
 }
 
+pub fn ir_type_encodable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream {
+    let encoder_ty = quote! { __E };
+    s.add_impl_generic(parse_quote! {#encoder_ty: crate::codec::TyEncoder});
+    s.add_bounds(synstructure::AddBounds::Fields);
+
+    encodable_body(s, encoder_ty, false)
+}
+
 pub fn type_encodable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream {
     if !s.ast().generics.lifetimes().any(|lt| lt.lifetime.ident == "tcx") {
         s.add_impl_generic(parse_quote! {'tcx});
     }
     let encoder_ty = quote! { __E };
     s.add_impl_generic(parse_quote! {#encoder_ty: ::rustc_type_ir::codec::TyEncoder<I = ::rustc_middle::ty::TyCtxt<'tcx>>});
-    s.add_bounds(synstructure::AddBounds::Generics);
+    s.add_bounds(synstructure::AddBounds::Fields);
 
     encodable_body(s, encoder_ty, false)
 }
@@ -107,15 +123,15 @@ pub fn meta_encodable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2:
     }
     s.add_impl_generic(parse_quote! { '__a });
     let encoder_ty = quote! { EncodeContext<'__a, 'tcx> };
-    s.add_bounds(synstructure::AddBounds::Generics);
+    s.add_bounds(synstructure::AddBounds::Fields);
 
     encodable_body(s, encoder_ty, true)
 }
 
 pub fn encodable_derive(mut s: synstructure::Structure<'_>) -> proc_macro2::TokenStream {
     let encoder_ty = quote! { __E };
     s.add_impl_generic(parse_quote! { #encoder_ty: ::rustc_serialize::Encoder});
-    s.add_bounds(synstructure::AddBounds::Generics);
+    s.add_bounds(synstructure::AddBounds::Fields);
 
     encodable_body(s, encoder_ty, false)
 }

compiler/rustc_middle/src/ty/sty.rs

@@ -15,6 +15,7 @@ use hir::def::DefKind;
 use polonius_engine::Atom;
 use rustc_data_structures::captures::Captures;
 use rustc_data_structures::intern::Interned;
+use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_index::vec::Idx;
@@ -1337,20 +1338,31 @@ impl fmt::Debug for EarlyBoundRegion {
 
 /// A **`const`** **v**ariable **ID**.
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
-#[derive(HashStable, TyEncodable, TyDecodable)]
+#[derive(TyEncodable, TyDecodable)]
 pub struct ConstVid<'tcx> {
     pub index: u32,
     pub phantom: PhantomData<&'tcx ()>,
 }
 
+impl<CTX> HashStable<CTX> for ConstVid<'_> {
+    fn hash_stable(&self, _: &mut CTX, _: &mut StableHasher) {
+        panic!("const variables should not be hashed: {self:?}")
+    }
+}
+
 rustc_index::newtype_index! {
     /// A **region** (lifetime) **v**ariable **ID**.
-    #[derive(HashStable)]
     pub struct RegionVid {
         DEBUG_FORMAT = custom,
     }
 }
 
+impl<CTX> HashStable<CTX> for RegionVid {
+    fn hash_stable(&self, _: &mut CTX, _: &mut StableHasher) {
+        panic!("region variables should not be hashed: {self:?}")
+    }
+}
+
 impl Atom for RegionVid {
     fn index(self) -> usize {
         Idx::index(self)

compiler/rustc_type_ir/src/lib.rs

@@ -502,6 +502,12 @@ rustc_index::newtype_index! {
     }
 }
 
+impl<CTX> HashStable<CTX> for TyVid {
+    fn hash_stable(&self, _: &mut CTX, _: &mut StableHasher) {
+        panic!("type variables should not be hashed: {self:?}")
+    }
+}
+
 /// An **int**egral (`u32`, `i32`, `usize`, etc.) type **v**ariable **ID**.
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Encodable, Decodable)]
 pub struct IntVid {