diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index 8545273afec..61c7698c59d 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -3386,6 +3386,7 @@ namespace ts {
          *      6) - UnaryExpression[?yield]
          *      7) ~ UnaryExpression[?yield]
          *      8) ! UnaryExpression[?yield]
+         *      9) await AwaitExpression[?yield]
          */
         function parseSimpleUnaryExpression(): UnaryExpression {
             switch (token) {
diff --git a/tests/baselines/reference/castOfAwait.js b/tests/baselines/reference/castOfAwait.js
index 8833a6aa972..9d1399d9d65 100644
--- a/tests/baselines/reference/castOfAwait.js
+++ b/tests/baselines/reference/castOfAwait.js
@@ -1,6 +1,9 @@
 //// [castOfAwait.ts]
 async function f() {
-    return <number> await 0;
+    <number> await 0;
+    typeof await 0;
+    void await 0;
+    await void <string> typeof <number> void await 0;
 }
 
 
@@ -15,6 +18,9 @@ var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, ge
 };
 function f() {
     return __awaiter(this, void 0, void 0, function* () {
-        return yield 0;
+        yield 0;
+        typeof yield 0;
+        void yield 0;
+        yield void typeof void yield 0;
     });
 }
diff --git a/tests/baselines/reference/castOfAwait.symbols b/tests/baselines/reference/castOfAwait.symbols
index b6ee77ac793..d0bca9f38c7 100644
--- a/tests/baselines/reference/castOfAwait.symbols
+++ b/tests/baselines/reference/castOfAwait.symbols
@@ -2,6 +2,9 @@
 async function f() {
 >f : Symbol(f, Decl(castOfAwait.ts, 0, 0))
 
-    return <number> await 0;
+    <number> await 0;
+    typeof await 0;
+    void await 0;
+    await void <string> typeof <number> void await 0;
 }
 
diff --git a/tests/baselines/reference/castOfAwait.types b/tests/baselines/reference/castOfAwait.types
index 7b6d8ef035b..ba1590fe03d 100644
--- a/tests/baselines/reference/castOfAwait.types
+++ b/tests/baselines/reference/castOfAwait.types
@@ -1,10 +1,30 @@
 === tests/cases/compiler/castOfAwait.ts ===
 async function f() {
->f : () => Promise<number>
+>f : () => Promise<void>
 
-    return <number> await 0;
+    <number> await 0;
 ><number> await 0 : number
 >await 0 : number
+>0 : number
+
+    typeof await 0;
+>typeof await 0 : string
+>await 0 : number
+>0 : number
+
+    void await 0;
+>void await 0 : undefined
+>await 0 : number
+>0 : number
+
+    await void <string> typeof <number> void await 0;
+>await void <string> typeof <number> void await 0 : any
+>void <string> typeof <number> void await 0 : undefined
+><string> typeof <number> void await 0 : string
+>typeof <number> void await 0 : string
+><number> void await 0 : number
+>void await 0 : undefined
+>await 0 : number
 >0 : number
 }
 
diff --git a/tests/baselines/reference/castOfYield.errors.txt b/tests/baselines/reference/castOfYield.errors.txt
new file mode 100644
index 00000000000..abafe678784
--- /dev/null
+++ b/tests/baselines/reference/castOfYield.errors.txt
@@ -0,0 +1,12 @@
+tests/cases/compiler/castOfYield.ts(4,14): error TS1109: Expression expected.
+
+
+==== tests/cases/compiler/castOfYield.ts (1 errors) ====
+    function* f() {
+        <number> (yield 0);
+        // Unlike await, yield is not allowed to appear in a simple unary expression.
+        <number> yield 0;
+                 ~~~~~
+!!! error TS1109: Expression expected.
+    }
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/castOfYield.js b/tests/baselines/reference/castOfYield.js
new file mode 100644
index 00000000000..652cf28e9e1
--- /dev/null
+++ b/tests/baselines/reference/castOfYield.js
@@ -0,0 +1,15 @@
+//// [castOfYield.ts]
+function* f() {
+    <number> (yield 0);
+    // Unlike await, yield is not allowed to appear in a simple unary expression.
+    <number> yield 0;
+}
+
+
+//// [castOfYield.js]
+function f() {
+    (yield 0);
+    // Unlike await, yield is not allowed to appear in a simple unary expression.
+    ;
+    yield 0;
+}
diff --git a/tests/cases/compiler/castOfAwait.ts b/tests/cases/compiler/castOfAwait.ts
index 64e96be70f3..6a152226ea2 100644
--- a/tests/cases/compiler/castOfAwait.ts
+++ b/tests/cases/compiler/castOfAwait.ts
@@ -1,4 +1,7 @@
 // @target: es6
 async function f() {
-    return <number> await 0;
+    <number> await 0;
+    typeof await 0;
+    void await 0;
+    await void <string> typeof <number> void await 0;
 }
diff --git a/tests/cases/compiler/castOfYield.ts b/tests/cases/compiler/castOfYield.ts
new file mode 100644
index 00000000000..9a85e6b21c2
--- /dev/null
+++ b/tests/cases/compiler/castOfYield.ts
@@ -0,0 +1,5 @@
+function* f() {
+    <number> (yield 0);
+    // Unlike await, yield is not allowed to appear in a simple unary expression.
+    <number> yield 0;
+}