Protected extension method on Object causes NPE in compiler

[rsmckinney]

• create an extension class on Object with protected extension method foo()
• call foo from an instance of any object
• NPE

java: An exception has occurred in the compiler (17.0.2). Please file a bug against the Java compiler via the Java bug reporting page (http://bugreport.java.com/) after checking the Bug Database (http://bugs.java.com/) for duplicates. Include your program, the following diagnostic, and the parameters passed to the Java compiler in your report. Thank you.
java: java.lang.NullPointerException: Cannot invoke "com.sun.tools.javac.code.Symbol$ClassSymbol.isSubClass(com.sun.tools.javac.code.Symbol, com.sun.tools.javac.code.Types)" because "c" is null
java:   at jdk.compiler/com.sun.tools.javac.comp.Lower.accessClass(Lower.java:1086)
java:   at jdk.compiler/com.sun.tools.javac.comp.Lower.accessSymbol(Lower.java:952)
java:   at jdk.compiler/com.sun.tools.javac.comp.Lower.access(Lower.java:1197)
java:   at jdk.compiler/com.sun.tools.javac.comp.Lower.visitSelect(Lower.java:4061)

(report from slack group by Jose Illescas: https://app.slack.com/client/T01385BBDLH/C012W174Z7V/thread/C012W174Z7V-1648578482.551389)

[rsmckinney]

fixed provided with release 2022.1.8