diff -r 894a3d15c344 -r e23e560afbcb src/jdk.compiler/share/classes/com/sun/tools/javac/code/Types.java
--- a/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Types.java	Thu Sep 26 04:20:19 2019 +0200
+++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Types.java	Wed Sep 25 21:26:38 2019 -0700
@@ -639,7 +639,7 @@
     public static class FunctionDescriptorLookupError extends RuntimeException {
         private static final long serialVersionUID = 0;
 
-        JCDiagnostic diagnostic;
+        transient JCDiagnostic diagnostic;
 
         FunctionDescriptorLookupError() {
             this.diagnostic = null;
@@ -5002,7 +5002,7 @@
         public static class InvalidSignatureException extends RuntimeException {
             private static final long serialVersionUID = 0;
 
-            private final Type type;
+            private final transient Type type;
 
             InvalidSignatureException(Type type) {
                 this.type = type;