From ce982a35e18e08b81a1524435f390b291f6e32b8 Mon Sep 17 00:00:00 2001
From: Taylor Yu <tlyu@mit.edu>
Date: Mon, 31 May 2021 19:58:15 -0500
Subject: [PATCH] debug for suggest_unsized_bound_if_applicable

---
 .../src/traits/error_reporting/mod.rs                | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
index 19c3385dd4c..f522e272ecf 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
@@ -1763,7 +1763,10 @@ impl<'a, 'tcx> InferCtxtPrivExt<'tcx> for InferCtxt<'a, 'tcx> {
                 ) => (pred, item_def_id, span),
                 _ => return,
             };
-
+        debug!(
+            "suggest_unsized_bound_if_applicable: pred={:?} item_def_id={:?} span={:?}",
+            pred, item_def_id, span
+        );
         let node = match (
             self.tcx.hir().get_if_local(item_def_id),
             Some(pred.def_id()) == self.tcx.lang_items().sized_trait(),
@@ -1775,6 +1778,11 @@ impl<'a, 'tcx> InferCtxtPrivExt<'tcx> for InferCtxt<'a, 'tcx> {
             Some(generics) => generics,
             None => return,
         };
+        debug!("suggest_unsized_bound_if_applicable: generics.params={:?}", generics.params);
+        debug!(
+            "suggest_unsized_bound_if_applicable: generics.where_clause={:?}",
+            generics.where_clause
+        );
         for param in generics.params {
             if param.span != span
                 || param.bounds.iter().any(|bound| {
@@ -1784,6 +1792,7 @@ impl<'a, 'tcx> InferCtxtPrivExt<'tcx> for InferCtxt<'a, 'tcx> {
             {
                 continue;
             }
+            debug!("suggest_unsized_bound_if_applicable: param={:?}", param);
             match node {
                 hir::Node::Item(
                     item
@@ -1895,6 +1904,7 @@ impl<'v> Visitor<'v> for FindTypeParam {
                 if path.segments.len() == 1 && path.segments[0].ident.name == self.param =>
             {
                 if !self.nested {
+                    debug!("FindTypeParam::visit_ty: ty={:?}", ty);
                     self.invalid_spans.push(ty.span);
                 }
             }