From 0a25bb58a4e2cdbe20cb0b38cef5f58920c8264c Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Sun, 6 Mar 2016 13:59:09 -0800
Subject: [PATCH] Make 'undefined' assignable to 'void'

---
 src/compiler/checker.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 853ca8d07be..9d05bc60c27 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -5507,7 +5507,7 @@ namespace ts {
 
                 if (isTypeAny(target)) return Ternary.True;
                 if (source.flags & TypeFlags.Undefined) {
-                    if (!strictNullChecks || target.flags & TypeFlags.Undefined || source === emptyArrayElementType) return Ternary.True;
+                    if (!strictNullChecks || target.flags & (TypeFlags.Undefined | TypeFlags.Void) || source === emptyArrayElementType) return Ternary.True;
                 }
                 if (source.flags & TypeFlags.Null) {
                     if (!strictNullChecks || target.flags & TypeFlags.Null) return Ternary.True;