src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/oops/Array.java

@@ -79,11 +79,13 @@
  
    private static long lengthOffsetInBytes() {
      if (lengthOffsetInBytes != 0) {
        return lengthOffsetInBytes;
      }
-     if (VM.getVM().isCompressedKlassPointersEnabled()) {
+     if (VM.getVM().isCompactObjectHeadersEnabled()) {
+       lengthOffsetInBytes = Oop.getHeaderSize();
+     } else if (VM.getVM().isCompressedKlassPointersEnabled()) {
        lengthOffsetInBytes = typeSize - VM.getVM().getIntSize();
      } else {
        lengthOffsetInBytes = typeSize;
      }
      return lengthOffsetInBytes;