From 9f50228981914193c5c92aa20eae689fdc49d139 Mon Sep 17 00:00:00 2001
From: dcode <dcode@dcode.io>
Date: Wed, 23 Mar 2022 00:45:39 +0100
Subject: [PATCH] Defuse assert when flattening after already diagnosing an
 error

---
 src/module.ts | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/module.ts b/src/module.ts
index 1375d86a44..16aa7c058b 100644
--- a/src/module.ts
+++ b/src/module.ts
@@ -1452,7 +1452,10 @@ export class Module {
         }
       }
       let singleType = getExpressionType(single);
-      assert(singleType == TypeRef.Unreachable || singleType == type);
+      if (singleType != TypeRef.Unreachable && singleType != type) {
+        // can happen when there was a diagnostic prior
+        return this.unreachable();
+      }
       return single;
     }
     return this.block(null, stmts, type);