Trust assignment fails for key with fingerprint ending in multiple zero blocks

[To Damon]

I don't know how to confirm it. This is a new secret key.

> gpg --list-secret-keys --with-fingerprint
gpg: DBG: Oops: keyid_from_fingerprint: no pubkey; fpr: 51f9e32f62fa6745c5cb09c2412a0000
gpg: DBG: Oops: keyid_from_fingerprint: no pubkey; fpr: 577e8f3f61625918c9c53c226b335000
gpg: key 0000000000000000 occurs more than once in the trustdb
gpg: checking the trustdb
gpg: Note: ultimately trusted key 0000000000000000 not found
gpg: no ultimately trusted keys found
/home/user/.gnupg/pubring.kbx


> gpg --export-options export-minimal --export 6B33500000000000 | gpg --list-packets
# off=0 ctb=98 tag=6 hlen=2 plen=51
:public key packet:
       version 4, algo 22, created 1723622837, expires 0
       pkey[0]: [80 bits] ed25519 (1.3.6.1.4.1.11591.15.1)
       pkey[1]: [263 bits]
       keyid: 6B33500000000000
# off=53 ctb=b4 tag=13 hlen=2 plen=27
:user ID packet: "Test (test) <test at test.dev>"
# off=82 ctb=88 tag=2 hlen=2 plen=144
:signature packet: algo 22, keyid 6B33500000000000
       version 4, created 1749823426, md5len 0, sigclass 0x13
       digest algo 10, begin of digest 56 1a
       hashed subpkt 33 len 21 (issuer fpr v4 577E8F3F61625918C9C53C226B33500000000000)
       hashed subpkt 2 len 4 (sig created 2025-06-13)
       hashed subpkt 27 len 1 (key flags: 23)
       hashed subpkt 11 len 4 (pref-sym-algos: 9 8 7 2)
       hashed subpkt 21 len 5 (pref-hash-algos: 10 9 8 11 2)
       hashed subpkt 22 len 3 (pref-zip-algos: 2 3 1)
       hashed subpkt 30 len 1 (features: 01)
       hashed subpkt 23 len 1 (keyserver preferences: 80)
       subpkt 16 len 8 (issuer key ID 6B33500000000000)
       data: [256 bits]
       data: [256 bits]

-----BEGIN PGP PRIVATE KEY BLOCK-----

lFgEZrxltRYJKwYBBAHaRw8BAQdA5YAyQLyr+9iU0vxkNHhZGprv18KrI8tPxWep
p4vH2W8AAP9+1De+ho5PeUTiDJAidUNt3PS2lYt8WmAvpiNsKIf2rhC+tBtUZXN0
ICh0ZXN0KSA8dGVzdEB0ZXN0LmRldj6IkAQTFgoAOBYhBFd+jz9hYlkYycU8Imsz
UAAAAAAABQJoTC/CAhsjBQsJCAcCBhUKCQgLAgQWAgMBAh4BAheAAAoJEGszUAAA
AAAAVhoBAMAWN3LHDK2BStO8jGyVZMTdN/VGCfVTtW0At1DSwe/dAQDlP0qpFm8V
oO5Wbk9U4x+VefbnQMiJQdh7KJGa60t/BA==
=qaQF
-----END PGP PRIVATE KEY BLOCK-----

> On 13 Jun 2025, at 21:54, Andrew Gallagher <andrewg at andrewg.com> wrote:
> 
> On 5 Jun 2025, at 10:24, To Damon via Gnupg-users <gnupg-users at gnupg.org> wrote:
>> 
>>> gpg --list-secret-keys --keyid-format=long --with-keygrip
>> gpg: DBG: Oops: keyid_from_fingerprint: no pubkey; fpr: ffffe32f62fa6745c5cb09c2412a0000
> 
> At some point it appears to have converted a v4 fingerprint with N>=32 trailing zero bits to a v3 fingerprint with N-32 trailing zero bits. Are fingerprints stored in a zero-padded fixed-width field somewhere?
> 
> A
>