Add inferred args to typeck

compiler/rustc_hir/src/intravisit.rs

@@ -437,7 +437,7 @@ pub trait Visitor<'v>: Sized {
         walk_label(self, label)
     }
     fn visit_infer(&mut self, inf: &'v InferArg) {
-        self.visit_id(inf.hir_id);
+        walk_inf(self, inf);
     }
     fn visit_generic_arg(&mut self, generic_arg: &'v GenericArg<'v>) {
         match generic_arg {
@@ -447,11 +447,6 @@ pub trait Visitor<'v>: Sized {
             GenericArg::Infer(inf) => self.visit_infer(inf),
         }
     }
-    /*
-    fn tcx(&self) -> Option<&TyCtxt<'tcx>> {
-        None
-    }
-    */
     fn visit_lifetime(&mut self, lifetime: &'v Lifetime) {
         walk_lifetime(self, lifetime)
     }

compiler/rustc_lint/src/late.rs

@@ -244,6 +244,11 @@ impl<'tcx, T: LateLintPass<'tcx>> hir_visit::Visitor<'tcx> for LateContextAndPas
         hir_visit::walk_ty(self, t);
     }
 
+    fn visit_infer(&mut self, inf: &'tcx hir::InferArg) {
+        lint_callback!(self, check_infer, inf);
+        hir_visit::walk_inf(self, inf);
+    }
+
     fn visit_name(&mut self, sp: Span, name: Symbol) {
         lint_callback!(self, check_name, sp, name);
     }

compiler/rustc_lint/src/passes.rs

@@ -33,6 +33,7 @@ macro_rules! late_lint_methods {
             fn check_expr(a: &$hir hir::Expr<$hir>);
             fn check_expr_post(a: &$hir hir::Expr<$hir>);
             fn check_ty(a: &$hir hir::Ty<$hir>);
+            fn check_infer(a: &$hir hir::InferArg);
             fn check_generic_arg(a: &$hir hir::GenericArg<$hir>);
             fn check_generic_param(a: &$hir hir::GenericParam<$hir>);
             fn check_generics(a: &$hir hir::Generics<$hir>);

compiler/rustc_middle/src/hir/map/mod.rs

@@ -272,11 +272,11 @@ impl<'hir> Map<'hir> {
                 GenericParamKind::Type { .. } => DefKind::TyParam,
                 GenericParamKind::Const { .. } => DefKind::ConstParam,
             },
-            Node::Infer(_) => todo!(),
             Node::Crate(_) => DefKind::Mod,
             Node::Stmt(_)
             | Node::PathSegment(_)
             | Node::Ty(_)
+            | Node::Infer(_)
             | Node::TraitRef(_)
             | Node::Pat(_)
             | Node::Binding(_)

compiler/rustc_middle/src/query/mod.rs

@@ -133,11 +133,6 @@ rustc_queries! {
         cache_on_disk_if { key.is_local() }
     }
 
-    query generic_arg_for_infer_arg(key: DefId) -> hir::GenericArg<'tcx> {
-        desc { |tcx| "computes concrete type for inference, `{}`", tcx.def_path_str(key) }
-        storage(ArenaCacheSelector<'tcx>)
-    }
-
     /// Maps from the `DefId` of an item (trait/struct/enum/fn) to the
     /// predicates (where-clauses) that must be proven true in order
     /// to reference it. This is almost always the "predicates query"

compiler/rustc_privacy/src/lib.rs

@@ -1191,16 +1191,7 @@ impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
     fn visit_generic_arg(&mut self, generic_arg: &'tcx hir::GenericArg<'tcx>) {
         match generic_arg {
             hir::GenericArg::Type(t) => self.visit_ty(t),
-            hir::GenericArg::Infer(inf) => {
-                self.span = inf.span;
-                let parent_hir_id = self.tcx.hir().get_parent_node(inf.hir_id);
-                if let Some(typeck_results) = self.maybe_typeck_results {
-                    let node_substs = typeck_results.node_substs(parent_hir_id);
-                    for ty in node_substs.types() {
-                        self.visit(ty);
-                    }
-                }
-            }
+            hir::GenericArg::Infer(inf) => self.visit_infer(inf),
             hir::GenericArg::Lifetime(_) | hir::GenericArg::Const(_) => {}
         }
     }
@@ -1224,6 +1215,23 @@ impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
         intravisit::walk_ty(self, hir_ty);
     }
 
+    fn visit_infer(&mut self, inf: &'tcx hir::InferArg) {
+        self.span = inf.span;
+        if let Some(typeck_results) = self.maybe_typeck_results {
+            if let Some(ty) = typeck_results.node_type_opt(inf.hir_id) {
+                if self.visit(ty).is_break() {
+                    return;
+                }
+            }
+        } else {
+            // FIXME see above note for same issue.
+            if self.visit(rustc_typeck::hir_ty_to_ty(self.tcx, &inf.to_ty())).is_break() {
+                return;
+            }
+        }
+        intravisit::walk_inf(self, inf);
+    }
+
     fn visit_trait_ref(&mut self, trait_ref: &'tcx hir::TraitRef<'tcx>) {
         self.span = trait_ref.path.span;
         if self.maybe_typeck_results.is_none() {

compiler/rustc_typeck/src/astconv/generics.rs

@@ -18,23 +18,6 @@ use rustc_session::lint::builtin::LATE_BOUND_LIFETIME_ARGUMENTS;
 use rustc_span::{symbol::kw, MultiSpan, Span};
 use smallvec::SmallVec;
 
-/*
-pub fn generic_arg_for_infer_arg<'tcx>(tcx: TyCtxt<'tcx>, did: LocalDefId) -> GenericArg<'tcx> {
-    todo!()
-    let hir_id = tcx.hir().local_def_id_to_hir_id(did);
-    let arg = match tcx.hir().get(hir_id) {
-        hir::Node::GenericParam(hir::GenericParam {
-            kind: hir::GenericParamKind::Const { ty: _, default: _ },
-            ..
-        }) => todo!(),
-        _ => bug!("Expected GenericParam for generic_arg_for_infer_arg"),
-    };
-
-    assert!(!matches!(arg, GenericArg::Infer(_)));
-    arg
-}
-*/
-
 impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
     /// Report an error that a generic argument did not match the generic parameter that was
     /// expected.

compiler/rustc_typeck/src/astconv/mod.rs

@@ -479,6 +479,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                                 param.def_id,
                                 Some(arg.id()),
                                 arg.span(),
+                                None,
                                 |_, _| {
                                     // Default generic parameters may not be marked
                                     // with stability attributes, i.e. when the

compiler/rustc_typeck/src/check/fn_ctxt/_impl.rs

@@ -581,6 +581,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
     }
 
+    pub fn node_ty_opt(&self, id: hir::HirId) -> Option<Ty<'tcx>> {
+        match self.typeck_results.borrow().node_types().get(id) {
+            Some(&t) => Some(t),
+            None if self.is_tainted_by_errors() => Some(self.tcx.ty_error()),
+            None => None,
+        }
+    }
+
     /// Registers an obligation for checking later, during regionck, that `arg` is well-formed.
     pub fn register_wf_obligation(
         &self,

compiler/rustc_typeck/src/check/writeback.rs

@@ -331,6 +331,15 @@ impl<'cx, 'tcx> Visitor<'tcx> for WritebackCx<'cx, 'tcx> {
         let ty = self.resolve(ty, &hir_ty.span);
         self.write_ty_to_typeck_results(hir_ty.hir_id, ty);
     }
+
+    fn visit_infer(&mut self, inf: &'tcx hir::InferArg) {
+        intravisit::walk_inf(self, inf);
+        // Ignore cases where the inference is a const.
+        if let Some(ty) = self.fcx.node_ty_opt(inf.hir_id) {
+            let ty = self.resolve(ty, &inf.span);
+            self.write_ty_to_typeck_results(inf.hir_id, ty);
+        }
+    }
 }
 
 impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> {

compiler/rustc_typeck/src/collect.rs

@@ -133,6 +133,7 @@ impl<'v> Visitor<'v> for PlaceholderHirTyCollector {
         match generic_arg {
             hir::GenericArg::Infer(inf) => {
                 self.0.push(inf.span);
+                intravisit::walk_inf(self, inf);
             }
             hir::GenericArg::Type(t) => self.visit_ty(t),
             _ => {}