hg: jdk/sandbox: 8236697: Stack overflow with cyclic hierarchy in class file

[chris.hegarty at oracle.com]

Changeset: 4176fe0a3cca
Author:    asotona
Date:      2020-06-08 16:07 -0400
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/4176fe0a3cca

8236697: Stack overflow with cyclic hierarchy in class file
Summary: Implemented minimal necessary cycle detection to avoid stack overflow in c.s.t.j.code.Types::asSuper
Reviewed-by: vromero

! src/jdk.compiler/share/classes/com/sun/tools/javac/code/Types.java
+ test/langtools/tools/javac/8236697/Cyclic.jcod
+ test/langtools/tools/javac/8236697/T8236697.java
+ test/langtools/tools/javac/8236697/T8236697.out