rustc_typeck: don't produce a DefId or Ty from rewrite_self_ctor, only a Def.

Author: eddyb

src/librustc_typeck/check/mod.rs

@@ -5330,7 +5330,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
     }
 
     // Rewrite `SelfCtor` to `Ctor`
-    pub fn rewrite_self_ctor(&self, def: Def, span: Span) -> (Def, DefId, Ty<'tcx>) {
+    pub fn rewrite_self_ctor(&self, def: Def, span: Span) -> Def {
         let tcx = self.tcx;
         if let Def::SelfCtor(impl_def_id) = def {
             let ty = self.impl_self_ty(span, impl_def_id).ty;
@@ -5340,8 +5340,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                 Some(adt_def) if adt_def.has_ctor() => {
                     let variant = adt_def.non_enum_variant();
                     let ctor_def_id = variant.ctor_def_id.unwrap();
-                    let def = Def::Ctor(ctor_def_id, CtorOf::Struct, variant.ctor_kind);
-                    (def, ctor_def_id, tcx.type_of(ctor_def_id))
+                    Def::Ctor(ctor_def_id, CtorOf::Struct, variant.ctor_kind)
                 }
                 _ => {
                     let mut err = tcx.sess.struct_span_err(span,
@@ -5364,16 +5363,11 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                     }
                     err.emit();
 
-                    (def, impl_def_id, tcx.types.err)
+                    def
                 }
             }
         } else {
-            let def_id = def.def_id();
-
-            // The things we are substituting into the type should not contain
-            // escaping late-bound regions, and nor should the base type scheme.
-            let ty = tcx.type_of(def_id);
-            (def, def_id, ty)
+            def
         }
     }
 
@@ -5396,7 +5390,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
 
         let tcx = self.tcx;
 
-        let (def, def_id, ty) = self.rewrite_self_ctor(def, span);
+        let def = self.rewrite_self_ctor(def, span);
         let path_segs = AstConv::def_ids_for_path_segments(self, segments, self_ty, def);
 
         let mut user_self_ty = None;
@@ -5501,6 +5495,20 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
             tcx.generics_of(*def_id).has_self
         }).unwrap_or(false);
 
+        let (def_id, ty) = if let Def::SelfCtor(impl_def_id) = def {
+            // NOTE(eddyb) an error has already been emitted by `rewrite_self_ctor`,
+            // avoid using the wrong type here. This isn't in `rewrite_self_ctor`
+            // itself because that runs too early (see #60989).
+            (impl_def_id, tcx.types.err)
+        } else {
+            let def_id = def.def_id();
+
+            // The things we are substituting into the type should not contain
+            // escaping late-bound regions, and nor should the base type scheme.
+            let ty = tcx.type_of(def_id);
+            (def_id, ty)
+        };
+
         let substs = AstConv::create_substs_for_generic_args(
             tcx,
             def_id,

src/test/compile-fail/issue-60989.rs

@@ -0,0 +1,18 @@
+struct A {}
+struct B {}
+
+impl From<A> for B {
+    fn from(a: A) -> B {
+        B{}
+    }
+}
+
+fn main() {
+    let c1 = ();
+    c1::<()>;
+    //~^ ERROR type arguments are not allowed for this type
+
+    let c1 = A {};
+    c1::<Into<B>>;
+    //~^ ERROR type arguments are not allowed for this type
+}

src/test/ui/issue-60989.rs

@@ -0,0 +1,15 @@
+error[E0109]: type arguments are not allowed for this type
+  --> $DIR/issue-60989.rs:12:10
+   |
+LL |     c1::<()>;
+   |          ^^ type argument not allowed
+
+error[E0109]: type arguments are not allowed for this type
+  --> $DIR/issue-60989.rs:16:10
+   |
+LL |     c1::<Into<B>>;
+   |          ^^^^^^^ type argument not allowed
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0109`.