Java ASM - Current frame's stack size doesn't match stackmap

I'm writing a stack-based esolang that compiles to JVM bytecode, but when I run a basic program, it errors with Current frame's stack size doesn't match stackmap. Full error:

Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.VerifyError: Instruction type does not match stack map
Exception Details:
  Location:
    Hello.main([Ljava/lang/String;)V @33: return
  Reason:
    Current frame's stack size doesn't match stackmap.
  Current Frame:
    bci: @33
    flags: { }
    locals: { '[Ljava/lang/String;', 'java/util/Scanner' }
    stack: { }
  Stackmap Frame:
    bci: @33
    flags: { }
    locals: { '[Ljava/lang/String;', 'java/util/Scanner' }
    stack: { integer }
  Bytecode:
    0x0000000: bb00 0959 b200 0fb7 0013 4c2b b600 1703
    0x0000010: b600 1d12 1e64 5999 000a b200 225f b600
    0x0000020: 28b1
  Stackmap Table:
    full_frame(@33,{Object[#42],Object[#9]},{Integer})

        at java.lang.Class.getDeclaredMethods0(Native Method)
        at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
        at java.lang.Class.privateGetMethodRecursive(Unknown Source)
        at java.lang.Class.getMethod0(Unknown Source)
        at java.lang.Class.getMethod(Unknown Source)
        at sun.launcher.LauncherHelper.validateMainClass(Unknown Source)
        at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)

Github (code is too large to put here): https://github.com/LengthLang/LengthJVM/blob/master/src/main/kotlin/com/nailuj29gaming/lengthjvm/Compile.kt Classfile: https://github.com/LengthLang/LengthJVM/blob/master/Hello.class