Implement Anonymous{Struct, Union} in the AST

Add unnamed_fields feature gate and gate unnamed fields on parsing

1 files changed, 13 insertions, 0 deletions

diff --git a/compiler/rustc_parse/src/parser/ty.rs b/compiler/rustc_parse/src/parser/ty.rs
index d537741c749..89cf2d7876e 100644
--- a/compiler/rustc_parse/src/parser/ty.rs
+++ b/compiler/rustc_parse/src/parser/ty.rs
@@ -226,6 +226,19 @@ impl<'a> Parser<'a> {
             }
         } else if self.eat_keyword(kw::Impl) {
             self.parse_impl_ty(&mut impl_dyn_multi)?
+        } else if self.token.is_keyword(kw::Union)
+            && self.look_ahead(1, |t| t == &token::OpenDelim(token::Brace))
+        {
+            self.bump();
+            let (fields, recovered) = self.parse_record_struct_body("union")?;
+            let span = lo.to(self.prev_token.span);
+            self.sess.gated_spans.gate(sym::unnamed_fields, span);
+            TyKind::AnonymousUnion(fields, recovered)
+        } else if self.eat_keyword(kw::Struct) {
+            let (fields, recovered) = self.parse_record_struct_body("struct")?;
+            let span = lo.to(self.prev_token.span);
+            self.sess.gated_spans.gate(sym::unnamed_fields, span);
+            TyKind::AnonymousStruct(fields, recovered)
         } else if self.is_explicit_dyn_type() {
             self.parse_dyn_ty(&mut impl_dyn_multi)?
         } else if self.eat_lt() {