A DESCRIPTION OF THE PROBLEM :
I see an infinite loop with with JDK 17 ea27/ea26 for pattern switch;
given switch pattern with guarded pattern case:
 
public class X {
  private static void foo(Object o) {
    switch (o) {
      case String s1 && s1.length()>1: System.out.println("Guarded"); break;
      default : System.out.println("Object");
    }
  }
   public static void main(String[] args) {
    foo(new Object());
  }
}
compiles fine with ea27 (and ea26), but while running gets into an infinite loop.

The disassembled code shows that there is a "goto 9" at 73 (to restart the switch) - I believe that this goto here is an error as switch need not be restarted at default; omitting the generation of this "goto" should remove the infinite loop.
 
 private static void foo(java.lang.Object arg0);
     ...
     9 aload_1
    10 iload_2
    11 invokedynamic 0 typeSwitch(java.lang.Object, int) : int [13]
    16 lookupswitch default: 65
          case 0: 36
    ....
    65 getstatic java.lang.System.out : java.io.PrintStream [23]
    68 ldc <String "Object"> [37]
    70 invokevirtual java.io.PrintStream.println(java.lang.String) : void [31]
    73 goto 9 <== this is an error
    76 return
 


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
javac --enable-preview --release 17 X.java; java --enable-preview X
where X.java is the code in description and javac/java are from 17 ea+27

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Object
ACTUAL -
Infinite loop printing object

---------- BEGIN SOURCE ----------
public class X {
  private static void foo(Object o) {
    switch (o) {
      case String s1 && s1.length()>1: System.out.println("Guarded"); break;
      default : System.out.println("Object");
    }
  }
   public static void main(String[] args) {
    foo(new Object());
  }
}
---------- END SOURCE ----------

FREQUENCY : always