diff --git a/src/execution/isolate.cc b/src/execution/isolate.cc
index 5b32d47bf9..c0549e462c 100644
--- a/src/execution/isolate.cc
+++ b/src/execution/isolate.cc
@@ -942,6 +942,14 @@ void CaptureAsyncStackTrace(Isolate* isolate, Handle<JSPromise> promise,
           PromiseCapability::cast(context->get(index)), isolate);
       if (!capability->promise().IsJSPromise()) return;
       promise = handle(JSPromise::cast(capability->promise()), isolate);
+    } else if (IsBuiltinFunction(isolate, reaction->fulfill_handler(),
+                                 Builtins::kPromiseCapabilityDefaultResolve)) {
+      Handle<JSFunction> function(JSFunction::cast(reaction->fulfill_handler()),
+                                  isolate);
+      Handle<Context> context(function->context(), isolate);
+      promise =
+          handle(JSPromise::cast(context->get(PromiseBuiltins::kPromiseSlot)),
+                 isolate);
     } else {
       // We have some generic promise chain here, so try to
       // continue with the chained promise on the reaction
diff --git a/test/mjsunit/async-stack-traces-realms.js b/test/mjsunit/async-stack-traces-realms.js
new file mode 100644
index 0000000000..9145b93377
--- /dev/null
+++ b/test/mjsunit/async-stack-traces-realms.js
@@ -0,0 +1,115 @@
+// Copyright 2019 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax --async-stack-traces
+
+// Basic test with an explicit throw.
+(function() {
+  const realm = Realm.createAllowCrossRealmAccess();
+
+  async function one(x) {
+    await two(x);
+  }
+
+  const two = Realm.eval(realm, `(async function two(x) {
+    await x;
+    throw new Error();
+  })`);
+
+  async function test(f) {
+    try {
+      await f(new Promise(resolve => setTimeout(resolve)));
+      assertUnreachable();
+    } catch (e) {
+      assertInstanceof(e, Realm.global(realm).Error);
+      assertMatches(/Error.+at two.+at async one.+at async test/ms, e.stack);
+    }
+  }
+
+  assertPromiseResult((async () => {
+    %PrepareFunctionForOptimization(one);
+    %PrepareFunctionForOptimization(two);
+    await test(one);
+    await test(one);
+    %OptimizeFunctionOnNextCall(two);
+    await test(one);
+    %OptimizeFunctionOnNextCall(one);
+    await test(one);
+    Realm.dispose(realm);
+  })());
+})();
+
+// Basic test with an implicit throw (via ToNumber on Symbol).
+(function() {
+  const realm = Realm.createAllowCrossRealmAccess();
+
+  async function one(x) {
+    return await two(x);
+  }
+
+  const two = Realm.eval(realm, `(async function two(x) {
+    await x;
+    return +Symbol();  // This will raise a TypeError.
+  })`);
+
+  async function test(f) {
+    try {
+      await f(new Promise(resolve => setTimeout(resolve)));
+      assertUnreachable();
+    } catch (e) {
+      assertInstanceof(e, Realm.global(realm).TypeError);
+      assertMatches(/TypeError.+at two.+at async one.+at async test/ms, e.stack);
+    }
+  }
+
+  assertPromiseResult((async() => {
+    %PrepareFunctionForOptimization(one);
+    %PrepareFunctionForOptimization(two);
+    await test(one);
+    await test(one);
+    %OptimizeFunctionOnNextCall(two);
+    await test(one);
+    %OptimizeFunctionOnNextCall(one);
+    await test(one);
+    Realm.dispose(realm);
+  })());
+})();
+
+// Basic test with async functions and promises chained via
+// Promise.prototype.then(), which should still work following
+// the generic chain upwards.
+(function() {
+  const realm = Realm.createAllowCrossRealmAccess();
+
+  async function one(x) {
+    return await two(x).then(x => x);
+  }
+
+  const two = Realm.eval(realm, `(async function two(x) {
+    await x.then(x => x);
+    throw new Error();
+  })`);
+
+  async function test(f) {
+    try {
+      await f(new Promise(resolve => setTimeout(resolve)));
+      assertUnreachable();
+    } catch (e) {
+      assertInstanceof(e, Realm.global(realm).Error);
+      assertMatches(/Error.+at two.+at async one.+at async test/ms, e.stack);
+    }
+  }
+
+  assertPromiseResult((async() => {
+    %PrepareFunctionForOptimization(one);
+    %PrepareFunctionForOptimization(two);
+    await test(one);
+    await test(one);
+    %OptimizeFunctionOnNextCall(two);
+    await test(one);
+    %OptimizeFunctionOnNextCall(one);
+    await test(one);
+    Realm.dispose(realm);
+  })());
+})();