autopkgtest fails in Hirsute

https://autopkgtest.ubuntu.com/packages/i/ipset/hirsute/amd64

https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac/autopkgtest-hirsute/hirsute/amd64/i/ipset/20210407_151236_9c93e@/log.gz
...
iphash: IP: Check listing: --- /dev/fd/61 2021-04-07 15:12:25.302346893 +0000
+++ /dev/fd/60 2021-04-07 15:12:25.302346893 +0000
@@ -1,8 +1,8 @@
 Name: test
 Type: hash:ip
 Revision: 5
-Header: family inet hashsize 128 maxelem 65536 bucketsize 12 initval 0x00000000
-Size in memory: 280
+Header: family inet hashsize 128 maxelem 65536
+Size in memory: 416
 References: 0
 Number of entries: 2
 Members:
FAILED
...