gpt problem on 5.1

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

I added a new hard disk and wanted to make a gpt label:
nas# gpt create /dev/wd3d
nas# gpt add -s 10486224 -t swap -i 1 /dev/wd3d
gpt: wd3d: error: no primary GPT header; run create or recover
nas# gpt show /dev/wd3d
       start        size  index  contents
           0           1         PMBR
           1  3907029134
  3907029135          32         Sec GPT table
  3907029167           1         Sec GPT header

Am I missing something obvious?
Is there a known bug in gpt in 5.1?

The kernel is from 5.1_STABLE, but I didn't update the userland --
just in case it matters.
 Thomas