test/java/lang/StackWalker/Basic.java

*** 72,81 ****
--- 72,116 ----
                               ConstructorNewInstance.class.getName()+"::create",
                               Basic.class.getName()+"::testWalkFromConstructor"),
                       found);
      }
  
+     @Test
+     public static void testMethodDescriptor() {
+         List<StackFrame> frames = new StackBuilder(16, 16).build();
+         for (StackFrame f : frames) {
+             System.out.format("%s.%s %s%n", f.getClassName(), f.getMethodName(),
+                               f.getMethodDescriptor());
+             switch (f.getMethodName()) {
+                 case "m1":
+                     if (!f.getMethodDescriptor().equals("()V")) {
+                         throw new RuntimeException("unexpected m1 descriptor: "
+                             + f.getMethodDescriptor());
+                     }
+                     break;
+                 case "m2":
+                     if (!f.getMethodDescriptor().equals("()Ljava/util/List;")) {
+                         throw new RuntimeException("unexpected m2 descriptor: "
+                             + f.getMethodDescriptor());
+                     }
+                     break;
+                 case "m3":
+                     if (!f.getMethodDescriptor().equals("()I")) {
+                         throw new RuntimeException("unexpected m3 descriptor: "
+                             + f.getMethodDescriptor());
+                     }
+                     break;
+                 case "m4":
+                     if (!f.getMethodDescriptor().equals("(Ljava/lang/Object;)V")) {
+                         throw new RuntimeException("unexpected m3 descriptor: "
+                             + f.getMethodDescriptor());
+                     }
+                     break;
+             }
+         }
+     }
+ 
      private final int depth;
      Basic(int depth) {
          this.depth = depth;
      }
  
*** 130,140 ****
          public static ConstructorNewInstance create() throws Exception {
              return ConstructorNewInstance.class.getConstructor().newInstance();
          }
      }
  
!     class StackBuilder {
          private final int stackDepth;
          private final int limit;
          private int depth = 0;
          private List<StackFrame> result;
          StackBuilder(int stackDepth, int limit) {
--- 165,175 ----
          public static ConstructorNewInstance create() throws Exception {
              return ConstructorNewInstance.class.getConstructor().newInstance();
          }
      }
  
!     static class StackBuilder {
          private final int stackDepth;
          private final int limit;
          private int depth = 0;
          private List<StackFrame> result;
          StackBuilder(int stackDepth, int limit) {
*** 148,166 ****
          }
          void m1() {
              trace("m1");
              m2();
          }
!         void m2() {
              trace("m2");
              m3();
          }
!         void m3() {
              trace("m3");
!             m4();
          }
!         void m4() {
              trace("m4");
              int remaining = stackDepth-depth-1;
              if (remaining >= 4) {
                  m1();
              } else {
--- 183,203 ----
          }
          void m1() {
              trace("m1");
              m2();
          }
!         List m2() {
              trace("m2");
              m3();
+             return null;
          }
!         int m3() {
              trace("m3");
!             m4(null);
!             return 0;
          }
!         void m4(Object o) {
              trace("m4");
              int remaining = stackDepth-depth-1;
              if (remaining >= 4) {
                  m1();
              } else {