From 7eb1a1afcfd5564f0d78f37c9c6397a070d794c2 Mon Sep 17 00:00:00 2001
From: Camelid <camelidcamel@gmail.com>
Date: Fri, 13 Nov 2020 11:23:12 -0800
Subject: [PATCH] Validate that locals have a corresponding `LocalDecl`

---
 compiler/rustc_mir/src/transform/validate.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/compiler/rustc_mir/src/transform/validate.rs b/compiler/rustc_mir/src/transform/validate.rs
index e1e6e71acb5a8..919e4a90a1716 100644
--- a/compiler/rustc_mir/src/transform/validate.rs
+++ b/compiler/rustc_mir/src/transform/validate.rs
@@ -183,6 +183,13 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
 
 impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
     fn visit_local(&mut self, local: &Local, context: PlaceContext, location: Location) {
+        if self.body.local_decls.get(*local).is_none() {
+            self.fail(
+                location,
+                format!("local {:?} has no corresponding declaration in `body.local_decls`", local),
+            );
+        }
+
         if self.reachable_blocks.contains(location.block) && context.is_use() {
             // Uses of locals must occur while the local's storage is allocated.
             self.storage_liveness.seek_after_primary_effect(location);