diff --git a/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/ThisEscapeAnalyzer.java b/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/ThisEscapeAnalyzer.java
index 7f7f09b3391..2dd054619e0 100644
--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/ThisEscapeAnalyzer.java
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/ThisEscapeAnalyzer.java
@@ -678,7 +678,11 @@ class ThisEscapeAnalyzer extends TreeScanner {
 
     @Override
     public void visitForeachLoop(JCEnhancedForLoop tree) {
-        visitLooped(tree, super::visitForeachLoop);
+        visitLooped(tree, foreach -> {
+            scan(foreach.expr);
+            refs.discardExprs(depth);       // we don't handle iterator() yet
+            scan(foreach.body);
+        });
     }
 
     @Override
@@ -729,7 +733,10 @@ class ThisEscapeAnalyzer extends TreeScanner {
 
     @Override
     public void visitLambda(JCLambda lambda) {
-        visitDeferred(() -> visitScoped(false, () -> super.visitLambda(lambda)));
+        visitDeferred(() -> visitScoped(false, () -> {
+            scan(lambda.body);
+            refs.discardExprs(depth);       // needed in case body is a JCExpression
+        }));
     }
 
     @Override
diff --git a/test/langtools/tools/javac/warnings/ThisEscape.java b/test/langtools/tools/javac/warnings/ThisEscape.java
index 65bca36923b..d6ae9f8e8f4 100644
--- a/test/langtools/tools/javac/warnings/ThisEscape.java
+++ b/test/langtools/tools/javac/warnings/ThisEscape.java
@@ -601,4 +601,20 @@ public class ThisEscape {
         public static final class Sub2 extends ThisEscapeSealed {
         }
     }
+
+    // Verify no assertion error occurs (JDK-8317336)
+    public static class ThisEscapeAssertionError {
+        public ThisEscapeAssertionError() {
+            System.out.println((Supplier<Object>)() -> this);
+        }
+    }
+
+    // Verify no assertion error occurs (JDK-8317336)
+    public static class ThisEscapeAssertionError2 {
+        public ThisEscapeAssertionError2() {
+            ThisEscapeAssertionError2[] array = new ThisEscapeAssertionError2[] { this };
+            for (Object obj : array)
+                ;
+        }
+    }
 }