main: locally disable a gcc warning since !672

I see no use to handle write() return codes in *this* function.
25 jobs for gcc-warning in 42 minutes and 29 seconds (queued for 7 seconds)
Status Job ID Name Coverage
  Build
passed #175701
amd64 linux docker
build:clang:linux:amd64

00:01:45

passed #175700
amd64 linux docker
build:linux:amd64

00:01:25

passed #175702
amd64 linux docker allowed to fail
srpm

00:01:26

 
  Test
passed #175709
amd64 linux docker
deckard:linux:amd64

00:01:29

passed #175714
privileged
distro:epel-7

00:02:04

passed #175713
privileged
distro:fedora-29

00:02:20

passed #175708
docker
doc

00:00:56

passed #175707
amd64 linux docker
installcheck:linux:amd64

00:01:13

passed #175710
amd64 linux docker
installcheck:valgrind:linux:amd64

00:01:51

passed #175704
docker
lint:c

00:02:31

failed #175705
docker allowed to fail
lint:clang-scan-build

00:01:16

passed #175703
docker
lint:lua

00:00:43

passed #175712
amd64 linux docker
respdiff:iter:udp:linux:amd64

00:02:13

passed #175706
amd64 linux docker
test:linux:amd64

00:01:11

passed #175711
amd64 linux docker
test:linux:amd64:valgrind

00:01:23

 
  Respdiff
failed #175715
respdiff
respdiff:fwd-tls6-kresd.udp6

00:23:11

failed #175716
respdiff
respdiff:fwd-udp6-kresd.udp6

00:32:11

failed #175720
respdiff
respdiff:fwd-udp6-unbound.tcp6

00:29:11

failed #175721
respdiff
respdiff:fwd-udp6-unbound.tls6

00:38:12

passed #175719
respdiff
respdiff:fwd-udp6-unbound.udp6

00:33:41

failed #175718
respdiff
respdiff:iter.tls6

00:17:35

passed #175717
respdiff
respdiff:iter.udp6

00:14:10

passed #175722
respdiff
resperf:fwd-tls6.udp-asan

00:23:01

passed #175723
respdiff
resperf:fwd-udp6.udp-asan

00:19:01

passed #175724
respdiff
resperf:iter.udp-asan

00:21:31

 
Name Stage Failure
failed
respdiff:fwd-tls6-kresd.udp6 Respdiff
~/builds/ea0ef08e/2/knot/knot-resolver
Running after script...
$ cp -t . respdiff_commitdir/$RESPDIFF_TEST/j* ||:
$ cp -t . respdiff_commitdir/*$RESPDIFF_TEST*.png ||:
Uploading artifacts...
./j*: found 9 matching files
./*.png: found 3 matching files

Uploading artifacts to coordinator... ok
id=175715 responseStatus=201 Created token=D5xJpZTz
ERROR: Job failed: exit status 1
failed
respdiff:fwd-udp6-kresd.udp6 Respdiff
~/builds/ea0ef08e/0/knot/knot-resolver
Running after script...
$ cp -t . respdiff_commitdir/$RESPDIFF_TEST/j* ||:
$ cp -t . respdiff_commitdir/*$RESPDIFF_TEST*.png ||:
Uploading artifacts...
./j*: found 9 matching files
./*.png: found 3 matching files

Uploading artifacts to coordinator... ok
id=175716 responseStatus=201 Created token=PMHrsqD8
ERROR: Job failed: exit status 1
failed
respdiff:fwd-udp6-unbound.tls6 Respdiff
~/builds/ea0ef08e/6/knot/knot-resolver
Running after script...
$ cp -t . respdiff_commitdir/$RESPDIFF_TEST/j* ||:
$ cp -t . respdiff_commitdir/*$RESPDIFF_TEST*.png ||:
Uploading artifacts...
./j*: found 9 matching files
./*.png: found 3 matching files

Uploading artifacts to coordinator... ok
id=175721 responseStatus=201 Created token=UjcwWXVY
ERROR: Job failed: exit status 1
failed
respdiff:fwd-udp6-unbound.tcp6 Respdiff
~/builds/ea0ef08e/5/knot/knot-resolver
Running after script...
$ cp -t . respdiff_commitdir/$RESPDIFF_TEST/j* ||:
$ cp -t . respdiff_commitdir/*$RESPDIFF_TEST*.png ||:
Uploading artifacts...
./j*: found 9 matching files
./*.png: found 3 matching files

Uploading artifacts to coordinator... ok
id=175720 responseStatus=201 Created token=CGyFYosx
ERROR: Job failed: exit status 1
failed
respdiff:iter.tls6 Respdiff
~/builds/ea0ef08e/3/knot/knot-resolver
Running after script...
$ cp -t . respdiff_commitdir/$RESPDIFF_TEST/j* ||:
$ cp -t . respdiff_commitdir/*$RESPDIFF_TEST*.png ||:
Uploading artifacts...
./j*: found 9 matching files
./*.png: found 3 matching files

Uploading artifacts to coordinator... ok
id=175718 responseStatus=201 Created token=EjwSfkjm
ERROR: Job failed: exit status 1
failed
lint:clang-scan-build Test
                                             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
5 warnings generated.
CCLD daemon/kresd
scan-build: 32 bugs found.
scan-build: Run 'scan-view /builds/knot/knot-resolver/scan-results/2018-09-17-102952-14-1' to examine bug reports.
Uploading artifacts...
scan-results: found 37 matching files
Uploading artifacts to coordinator... ok
id=175705 responseStatus=201 Created token=W_ZQsz_5
ERROR: Job failed: exit code 1