Help getting minimal native image shared library to work

[ahelwer]

My question appears similar to #2193. I have the following simple Java file:

package tla;

import org.graalvm.nativeimage.IsolateThread;
import org.graalvm.nativeimage.ObjectHandle;
import org.graalvm.nativeimage.ObjectHandles;
import org.graalvm.nativeimage.c.function.CEntryPoint;
import org.graalvm.nativeimage.c.type.CTypeConversion;
import org.graalvm.nativeimage.c.type.CTypeConversion.CCharPointerHolder;

public class Lib {
  @CEntryPoint(name = "get_message")
  public static ObjectHandle getMessage(
      @CEntryPoint.IsolateThreadContext IsolateThread thread
  ) {
    String result = Lib.getMessage();
    try (CCharPointerHolder cstr = CTypeConversion.toCString(result)) {
      return ObjectHandles.getGlobal().create(cstr);
    }
  }
  
  public static String getMessage() {
    return "Hello, world!";
  }
}

Then I downloaded nativeimage-24.2.1.jar from maven central. If I run javac Lib.java -cp nativeimage-24.2.1.jar it outputs a Lib.class file. Then I run native-image --shared -o TlaLib -cp Lib.class and it outputs a TlaLib.so file along with header files. However, I cannot find the get_message function defined in either the .so file or the header files. What am I doing wrong? Thank you for any help you can provide.