Migration fails with "ghc table does not exist"

[ajm188]

This was running off of master against an 8.4.6 database.

+ ./gh-ost -allow-on-master -attempt-instant-ddl -dml-batch-size 50 -exact-rowcount -force-named-cut-over -force-named-panic -postpone-cut-over-flag-file /tmp/queries/bb2d953d-431d-4bf0-
b6b2-d7ed1a2ae9d0/postpone-cutover -throttle-additional-flag-file /tmp/queries/bb2d953d-431d-4bf0-b6b2-d7ed1a2ae9d0/throttle -timestamp-old-table --skip-metadata-lock-check -database test -alter 'add index idx_user_start_time_end_time (user_id, start_time, end_time)' -table queries -host $hostname -user root -ask-pass
[2026/01/30 17:57:10] [info] binlogsyncer.go:191 create BinlogSyncer with config {ServerID:99999 Flavor:mysql Host:[redacted] Port:3306 User:root Password: Localhost: Charset: SemiSyncEnabled:false RawModeEnabled:false TLSConfig:<nil> ParseTime:false TimestampStringLocation:UTC UseDecimal:true RecvB
ufferSize:0 HeartbeatPeriod:0s ReadTimeout:0s MaxReconnectAttempts:0 DisableRetrySync:false VerifyChecksum:false DumpCommandFlag:0 Option:<nil> Logger:0x40004c23c0 Dialer:0x329d40 RowsEv
entDecodeFunc:<nil> TableMapOptionalMetaDecodeFunc:<nil> DiscardGTIDSet:false EventCacheCount:10240 SynchronousEventHandler:<nil>}
[2026/01/30 17:57:10] [info] binlogsyncer.go:443 begin to sync binlog from position (mysql-bin-changelog.027237, 3002)
[2026/01/30 17:57:10] [info] binlogsyncer.go:409 Connected to mysql 8.4.6 server
[2026/01/30 17:57:10] [info] binlogsyncer.go:868 rotate to (mysql-bin-changelog.027237, 3002)
# Migrating `test`.`queries`; Ghost table is `test`.`_queries_gho`
# Migrating `test`.`queries`; Ghost table is `test`.`_queries_gho`
# Migrating ip-172-17-5-122:3306; inspecting ip-172-17-5-122:3306; executing on bastion-0
# Migration started at Fri Jan 30 17:57:10 +0000 2026
# chunk-size: 1000; max-lag-millis: 1500ms; dml-batch-size: 50; max-load: ; critical-load: ; nice-ratio: 0.000000
# throttle-additional-flag-file: /tmp/queries/bb2d953d-431d-4bf0-b6b2-d7ed1a2ae9d0/throttle
# postpone-cut-over-flag-file: /tmp/queries/bb2d953d-431d-4bf0-b6b2-d7ed1a2ae9d0/postpone-cutover [set]
# Serving on unix socket: /tmp/gh-ost.test.queries.sock
# Migrating ip-172-17-5-122:3306; inspecting ip-172-17-5-122:3306; executing on bastion-0
# Migration started at Fri Jan 30 17:57:10 +0000 2026
# chunk-size: 1000; max-lag-millis: 1500ms; dml-batch-size: 50; max-load: ; critical-load: ; nice-ratio: 0.000000
# throttle-additional-flag-file: /tmp/queries/bb2d953d-431d-4bf0-b6b2-d7ed1a2ae9d0/throttle
# postpone-cut-over-flag-file: /tmp/queries/bb2d953d-431d-4bf0-b6b2-d7ed1a2ae9d0/postpone-cutover [set]
# Serving on unix socket: /tmp/gh-ost.honeycomb_prod.queries.sock
Copy: 0/0 100.0%; Applied: 0; Backlog: 0/1000; Time: 0s(total), 0s(copy); streamer: mysql-bin-changelog.027237:7368; Lag: 0.07s, HeartbeatLag: 0.07s, State: migrating; ETA: due
Copy: 0/426432577 0.0%; Applied: 0; Backlog: 0/1000; Time: 0s(total), 0s(copy); streamer: mysql-bin-changelog.027237:7368; Lag: 0.07s, HeartbeatLag: 0.07s, State: migrating; ETA: N/A
CREATE TABLE `_queries_gho` (
  `id` int NOT NULL AUTO_INCREMENT,
  ...
  PRIMARY KEY (`id`),
) ENGINE=InnoDB AUTO_INCREMENT=404517417 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin
[2026/01/30 17:57:10] [info] binlogsyncer.go:225 syncer is closing...
[2026/01/30 17:57:10] [info] binlogsyncer.go:988 kill last connection id 109
[2026/01/30 17:57:10] [info] binlogsyncer.go:255 syncer is closed
2026-01-30 17:57:10 ERROR Error 1146 (42S02): Table 'test._queries_ghc' doesn't exist

Interestingly, I was not running in either "revert" or "resume" mode, so I have no idea why gh-ost didn't actually try to create the changelog table. After the gh-ost process exited, there were no gh-ost tables on the database at all:

(MySQL):test>show tables like '%gh%';
+---------------------------------+
| Tables_in_test (%gh%) |
+---------------------------------+
+---------------------------------+