PostgreSQL 12 crash with segmentation violation

Hi,

I'm using posgreSQL for many years, all versions like 9x, 10x, 11x - thank you very much for this excellent piece of software.

Now I have upgraded to postgresql 12 and get a crash about once per day, unfortunately our midleware (Java via current JDBC) stops immediately on this and all users are offline.

In  pg_log/postgresql-2019-10-31.csv I find entries like:

2019-10-31 07:03:03.750 CET,,,1516,,5db5cfa5.5ec,19,,2019-10-27 18:11:01 CET,,0,LOG,00000,"server process (PID 27439) was terminated by signal 11: Speicherzugriffsfehler","Failed proc
ess was running: update Location set enmea=$1, guid=$2, latDeci=$3, lonDeci=$4, modifiedByLoginName=$5, poiObjectId=$6, timestamp=$7, TRACK_ID=$8 where LOCATION_ID=$9",,,,,,,,""

I have built postgresql from source on a current Debian Linux with

./configure --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu --with-pam --with-openssl --with-libxml –with-libxslt –with-llvm

td p { background: transparent none repeat scroll 0% 0%; }p { margin-bottom: 0.25cm; line-height: 120%; background: transparent none repeat scroll 0% 0%; }code.western { font-family: "Liberation Mono", monospace; }code.cjk { font-family: "Droid Sans Fallback", monospace; }code.ctl { font-family: "Liberation Mono", monospace; }a:link { color: rgb(0, 0, 128); text-decoration: underline; }a:visited { color: rgb(128, 0, 0); text-decoration: underline; }

Additionally postgis is compiled into and a little own c library (language C strict) is used.

I have already disabled llvm with jit = off which didn't help.

How can I track down the problem?

thank you
Marcel