diff --git a/spec.html b/spec.html
index a7eac67b829..10fae57d77c 100644
--- a/spec.html
+++ b/spec.html
@@ -38264,7 +38264,10 @@
%AsyncFromSyncIteratorPrototype%.next ( _value_ )
1. Assert: Type(_O_) is Object and _O_ has a [[SyncIteratorRecord]] internal slot.
1. Let _promiseCapability_ be ! NewPromiseCapability(%Promise%).
1. Let _syncIteratorRecord_ be _O_.[[SyncIteratorRecord]].
- 1. Let _result_ be IteratorNext(_syncIteratorRecord_, _value_).
+ 1. If _value_ is present, then
+ 1. Let _result_ be IteratorNext(_syncIteratorRecord_, _value_).
+ 1. Else,
+ 1. Let _result_ be IteratorNext(_syncIteratorRecord_).
1. IfAbruptRejectPromise(_result_, _promiseCapability_).
1. Return ! AsyncFromSyncIteratorContinuation(_result_, _promiseCapability_).
@@ -38284,7 +38287,10 @@ %AsyncFromSyncIteratorPrototype%.return ( _value_ )
1. Let _iterResult_ be ! CreateIterResultObject(_value_, *true*).
1. Perform ! Call(_promiseCapability_.[[Resolve]], *undefined*, « _iterResult_ »).
1. Return _promiseCapability_.[[Promise]].
- 1. Let _result_ be Call(_return_, _syncIterator_, « _value_ »).
+ 1. If _value_ is present, then
+ 1. Let _result_ be Call(_return_, _syncIterator_, « _value_ »).
+ 1. Else,
+ 1. Let _result_ be Call(_return_, _syncIterator_, « »).
1. IfAbruptRejectPromise(_result_, _promiseCapability_).
1. If Type(_result_) is not Object, then
1. Perform ! Call(_promiseCapability_.[[Reject]], *undefined*, « a newly created *TypeError* object »).
@@ -38306,7 +38312,10 @@ %AsyncFromSyncIteratorPrototype%.throw ( _value_ )
1. If _throw_ is *undefined*, then
1. Perform ! Call(_promiseCapability_.[[Reject]], *undefined*, « _value_ »).
1. Return _promiseCapability_.[[Promise]].
- 1. Let _result_ be Call(_throw_, _syncIterator_, « _value_ »).
+ 1. If _value_ is present, then
+ 1. Let _result_ be Call(_throw_, _syncIterator_, « _value_ »).
+ 1. Else,
+ 1. Let _result_ be Call(_throw_, _syncIterator_, « »).
1. IfAbruptRejectPromise(_result_, _promiseCapability_).
1. If Type(_result_) is not Object, then
1. Perform ! Call(_promiseCapability_.[[Reject]], *undefined*, « a newly created *TypeError* object »).