I try the following code when solving the JDK-8267610.

```
class Main {
    String test(Object o) {
        if (o instanceof (CharSequence cs && cs instanceof String s)){
            return s;
        }
        return null;
    }
}
```

The javac compiles successfully and generates the following bytecode.

```
  java.lang.String test(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Ljava/lang/String;
    flags: (0x0000)
    Code:
      stack=1, locals=4, args_size=2
         0: aload_1
         1: instanceof #7 // class java/lang/CharSequence
         4: ifeq 26
         7: aload_1
         8: checkcast #7 // class java/lang/CharSequence
        11: astore_2
        12: aload_1 // <---------- should be `aload_2`
        13: instanceof #9 // class java/lang/String
        16: ifeq 26
        19: aload_1 // <---------- should be `aload_2`
        20: checkcast #9 // class java/lang/String
        23: astore_3
        24: aload_3
        25: areturn
        26: aconst_null
        27: areturn
```

There are two wrong places where I mark "// <---------- should be `aload_2`".

After fixing JDK-8267610 locally, javac generates the following byte code:

```
  java.lang.String test(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Ljava/lang/String;
    flags: (0x0000)
    Code:
      stack=1, locals=4, args_size=2
         0: aload_1
         1: instanceof #7 // class java/lang/CharSequence
         4: ifeq 26
         7: aload_1
         8: checkcast #7 // class java/lang/CharSequence
        11: astore_2
        12: aload_2
        13: instanceof #9 // class java/lang/String
        16: ifeq 26
        19: aload_1 // <---------- should be `aload_2`
        20: checkcast #9 // class java/lang/String
        23: astore_3
        24: aload_3
        25: areturn
        26: aconst_null
        27: areturn
```

One wrong byte code is also generated.

Both JDK-8267610 and this issue are caused by the BindingPattern and BindingSymbol.
During desugar, especially TransPatterns, we shouldn't make a tree which contains JCBindingPattern or BindingSymbol. So after desugar, the whole AST shouldn't contain JCBindingPattern or BindingSymbol anymore.
If not, the tree is wrong and the javac may crash or generate wrong bytecode unexpectedly.