In the manpage for sem_wait(3) in the NOTES sections says that sem_wait can be interrupted by a signal despite using the SA_RESTART flag. The manpage for signal(7) states the opposite, that a blocking call of sem_wait and sem_timedwait will be automatically restarted if the signal handler uses the SA_RESTART flag.
signal(7) is correct. The text in sem-wait(3) is out of date. I removed that text. Closing this now. Thanks for the report.