After updating hddtemp to app-admin/hddtemp-0.3_beta15-r27, some of my hosts are no longer able to read the disk temperature sensor. r28 (current stable) is also affected. r26 worked fine. Smartctl also works fine.
# hddtemp /dev/sda
/dev/sda: ATA SAMSUNG HD501LJ: drive supported, but it doesn't have a temperature sensor.
# hddtemp -D /dev/sda
================= hddtemp 0.3-beta15 ==================
Model: ATA SAMSUNG HD501LJ
If one of the field value seems to match the temperature, be sure to read
the hddtemp man page before sending a report (section REPORT). Thanks.
# smartctl -a /dev/sda | grep Temp
190 Airflow_Temperature_Cel 0x0022 077 065 000 Old_age Always - 23
194 Temperature_Celsius 0x0022 169 133 000 Old_age Always - 23
I noticed that r27 started using debian patchset 53 (https://ftp.rnl.tecnico.ulisboa.pt/pub/debian/pool/main/h/hddtemp/), as per https://bugs.gentoo.org/627272 . That's probably related.
I'm happy to provide strace logs or follow additional steps to debug this. Thanks in advance.