BUG #14902: valgrind - problem in PQconnectdb - pqSaveParameterStatus reported

The following bug has been logged on the website:

Bug reference: 14902
Logged by: Pavel Bazika
Email address: pavel(dot)bazika(at)kocovnici(dot)cz
PostgreSQL version: 10.1
Operating system: Arch Linux
Description:

Hi,

I'm testing my application with helgrind threading error detection tool
(part of valgrind) and it reports a problem in libpq, when I'm calling
PQconnectdb from two threads:

==25830== Possible data race during write of size 4 at 0x7D600CC by thread
#1
==25830== Locks held: none
==25830== at 0x7B2CFE4: pqSaveParameterStatus (fe-exec.c:1022)
==25830== by 0x7B35A01: getParameterStatus (fe-protocol3.c:1378)
==25830== by 0x7B36E77: pqParseInput3 (fe-protocol3.c:265)
==25830== by 0x7B2DD7D: PQisBusy (fe-exec.c:1738)
==25830== by 0x7B274D6: PQconnectPoll (fe-connect.c:2909)
==25830== by 0x7B2829D: connectDBComplete.part.9 (fe-connect.c:1931)
==25830== by 0x7B2B31F: connectDBComplete (fe-connect.c:589)
==25830==
==25830== This conflicts with a previous write of size 4 by thread #4
==25830== Locks held: none
==25830== at 0x7B2CFE4: pqSaveParameterStatus (fe-exec.c:1022)
==25830== by 0x7B35A01: getParameterStatus (fe-protocol3.c:1378)
==25830== by 0x7B36E77: pqParseInput3 (fe-protocol3.c:265)
==25830== by 0x7B2DD7D: PQisBusy (fe-exec.c:1738)
==25830== by 0x7B274D6: PQconnectPoll (fe-connect.c:2909)
==25830== by 0x7B2829D: connectDBComplete.part.9 (fe-connect.c:1931)
==25830== by 0x7B2B31F: connectDBComplete (fe-connect.c:589)
==25830== by 0x7B2B31F: PQconnectdb (fe-connect.c:590)

and

==25830== Possible data race during write of size 1 at 0x7D600C8 by thread
#1
==25830== Locks held: none
==25830== at 0x7B2CFC3: pqSaveParameterStatus (fe-exec.c:1027)
==25830== by 0x7B35A01: getParameterStatus (fe-protocol3.c:1378)
==25830== by 0x7B36E77: pqParseInput3 (fe-protocol3.c:265)
==25830== by 0x7B2DD7D: PQisBusy (fe-exec.c:1738)
==25830== by 0x7B274D6: PQconnectPoll (fe-connect.c:2909)
==25830== by 0x7B2829D: connectDBComplete.part.9 (fe-connect.c:1931)
==25830== by 0x7B2B31F: connectDBComplete (fe-connect.c:589)
==25830== by 0x7B2B31F: PQconnectdb (fe-connect.c:590)
==25830==
==25830== This conflicts with a previous write of size 1 by thread #4
==25830== Locks held: none
==25830== at 0x7B2CFC3: pqSaveParameterStatus (fe-exec.c:1027)
==25830== by 0x7B35A01: getParameterStatus (fe-protocol3.c:1378)
==25830== by 0x7B36E77: pqParseInput3 (fe-protocol3.c:265)
==25830== by 0x7B2DD7D: PQisBusy (fe-exec.c:1738)
==25830== by 0x7B274D6: PQconnectPoll (fe-connect.c:2909)
==25830== by 0x7B2829D: connectDBComplete.part.9 (fe-connect.c:1931)
==25830== by 0x7B2B31F: connectDBComplete (fe-connect.c:589)
==25830== by 0x7B2B31F: PQconnectdb (fe-connect.c:590)

Is this false positive, bug or am I doing something wrong? The problem
occurrs when those static variables are written in fe-exex.c.

Thanks