GPSD doesn't report signal dropout

[Tom Isaacson]

We are using gpsd 3.19 on a Quectel EC25 Mini PCIe
(https://www.quectel.com/product/eg25g.htm). GPS seems to work fine
until we lose the signal (e.g. go into a tunnel).

The NMEA0183 output shows when I disconnect/reconnect the antenna:
https://www.dropbox.com/s/4se0nluw8yh33fr/nmea-disconnect.txt?dl=0
See $GPRMC validity (http://aprs.gids.nl/nmea/#rmc) change from A (ok)
to V (invalid) and back again.

The GPSD log shows the same - you can see the lock disappear and reappear:
https://www.dropbox.com/s/9fx48cohioepv06/gpsd-disconnect.txt?dl=0

But the client app never sees the dropout:
https://www.dropbox.com/s/yu7mcfmz8dps01e/gpsd-api-disconnect.txt?dl=0

Any suggestions? Is this a known bug, have we just compiled with the
wrong flags, what?

Thanks.

Tom Isaacson