Following class compiled with --enable-preview:
---
public class T {

    static void m(java.util.function.Consumer<Object> cons) {}

    public static void main(String[] args) {
        m(o -> {
            if (o instanceof CharSequence chs) {
                switch (chs) {
                    default -> {}
                }
            }
        });
    }
}

---
Fails to initialize due to invalid stack map:
---
Error: Unable to initialize main class T
Caused by: java.lang.VerifyError: Bad local variable type
Exception Details:
  Location:
    T.lambda$main$0(Ljava/lang/Object;)V @12: aload_2
  Reason:
    Type top (current frame, locals[2]) is not assignable to reference type
  Current Frame:
    bci: @12
    flags: { }
    locals: { 'java/lang/Object', 'java/lang/CharSequence' }
    stack: { }
  Bytecode:
    0000000: 2ac1 0011 9900 242a c000 114c 2c59 b800
    0000010: 1357 4d03 3e2c 1dba 0019 0000 ab00 0000
    0000020: 0000 000c 0000 0000 b1
  Stackmap Table:
    append_frame(@21,Object[#17],Object[#17],Integer)
    chop_frame(@40,3)