From 95b853cc74fc7a36dd92f163a8660ee6f1b6ff87 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sat, 23 May 2020 17:54:26 +0200
Subject: [PATCH] more type sanity checks in Miri

---
 src/librustc_mir/interpret/operand.rs | 7 +++++++
 src/librustc_mir/interpret/place.rs   | 7 +++++++
 2 files changed, 14 insertions(+)

diff --git a/src/librustc_mir/interpret/operand.rs b/src/librustc_mir/interpret/operand.rs
index f546f6236d777..1283f55cb2d33 100644
--- a/src/librustc_mir/interpret/operand.rs
+++ b/src/librustc_mir/interpret/operand.rs
@@ -469,6 +469,13 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             .try_fold(base_op, |op, elem| self.operand_projection(op, elem))?;
 
         trace!("eval_place_to_op: got {:?}", *op);
+        // Sanity-check the type we ended up with.
+        debug_assert_eq!(
+            self.subst_from_current_frame_and_normalize_erasing_regions(
+                place.ty(&self.frame().body.local_decls, *self.tcx).ty
+            ),
+            op.layout.ty,
+        );
         Ok(op)
     }
 
diff --git a/src/librustc_mir/interpret/place.rs b/src/librustc_mir/interpret/place.rs
index 6dadb8e4c67f4..6a64cd3ade8f3 100644
--- a/src/librustc_mir/interpret/place.rs
+++ b/src/librustc_mir/interpret/place.rs
@@ -638,6 +638,13 @@ where
         }
 
         self.dump_place(place_ty.place);
+        // Sanity-check the type we ended up with.
+        debug_assert_eq!(
+            self.subst_from_current_frame_and_normalize_erasing_regions(
+                place.ty(&self.frame().body.local_decls, *self.tcx).ty
+            ),
+            place_ty.layout.ty,
+        );
         Ok(place_ty)
     }