The known issue with OpenBSD 6.8 builders appears to be resolved
via CL 278732 and CL 279134. Promote them to the primary OpenBSD
post-submit builders and TryBots.

Having test coverage from OpenBSD 6.8 and 6.4 builders gives us
us more confidence that Go works on supported OpenBSD versions
(which are 6.8 and 6.7 at this time, per past policy decision
in https://golang.org/issue/15227#issuecomment-293319876).

Reduce numTryTestHelpers from 5 to 4 based on some data from
golang.org/issue/37439 showing that going from 3 to 5 helpers
doesn't make a significant difference. We can adjust further
if we learn that OpenBSD TryBots become the bottleneck.

Fixes golang/go#35712.
For golang/go#42542.
For golang/go#42064.
Updates golang/go#42426.

Change-Id: Id2fa4be7c3161f89752c1428146846fe06ca63db
Reviewed-on: https://go-review.googlesource.com/c/build/+/279512
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Alexander Rakoczy <alex@golang.org>
Trust: Dmitri Shuralyov <dmitshur@golang.org>

These tests are known to be failing on OpenBSD 6.8 and need
investigation. The OpenBSD 6.8 builders are default TryBots
now, so skip them to prevent people working on other packages
from constantly getting a failure.

Issue 42064 remains open to do the work of determining if the
ipv6 package needs to be fixed, or if OpenBSD 6.8 has a problem
and the test can be permanently skipped as unsupported.

For golang/go#11811.
Updates golang/go#42064.
Updates golang/go#35712.

Change-Id: I59883384e4dbce679cb1a4e8e2c3f0fa7983010b
Reviewed-on: https://go-review.googlesource.com/c/net/+/280052
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Alexander Rakoczy <alex@golang.org>
Trust: Dmitri Shuralyov <dmitshur@golang.org>

…ilders

The arm64 and mips64 builder run OpenBSD 6.8:

openbsd-arm64-jsing:
OpenBSD gopher-arm64.sing.id.au 6.8 GENERIC.MP#2 arm64

openbsd-mips64-jsing:
OS: OpenBSD er4.sing.id.au 6.8 GENERIC.MP#0 octeon

The openbsd-arm-jsing builder was offline but according to
golang/go#25498 (comment)
it's running at least OpenBSD 6.7. Assuming that this version is
affected as well (or the builder was upgraded to 6.8 in the meantime),
skip TestPacketConnReadWriteMulticastUDP on this builder as well.

For golang/go#11811.
Updates golang/go#42064.

Change-Id: Ia9919057bfc2a69b8884228508ae919ce9d624e9
Reviewed-on: https://go-review.googlesource.com/c/net/+/283752
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Joel Sing <joel@sing.id.au>

Instead of relying on syscall.Syscall, always reach into the syscall
package to call the appropriate functions on Unix systems. We were
already doing this on Darwin. We also have to do this on
OpenBSD. Rather than sometimes reach into syscall and sometimes not,
just always reach in.

For golang/go#42064

Change-Id: Ie292a56766080d0c5ae6b6723d42b5475128290c
Reviewed-on: https://go-review.googlesource.com/c/net/+/366354
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>

Instead of relying on syscall.Syscall, always reach into the syscall
package to call the appropriate functions on Unix systems. We were
already doing this on Darwin and AIX. We also have to do this on
OpenBSD, and it's simpler to do it on Linux 386 and s390x. Rather than
sometimes reach into syscall and sometimes not, just always reach in.

For golang/go#42064

Change-Id: I0adb1c7cc623f2c1247465b3852fefd8d09975d2
Reviewed-on: https://go-review.googlesource.com/c/net/+/366195
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>

This brings in a fix for OpenBSD that lets it correctly gather network
interface information.

For #42064

Change-Id: Ib88fd2f494bb2ee86fd2725d8375b2df1404c4ca
Reviewed-on: https://go-review.googlesource.com/c/go/+/366756
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>

…ort multicast loopback

Skip the tests for it, as we already skip them on FreeBSD.

For golang/go#42064
For golang/go#49908

Change-Id: I058f25309020367e686625033b4f25cb614c7f99
Reviewed-on: https://go-review.googlesource.com/c/net/+/366355
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-on: https://go-review.googlesource.com/c/net/+/368514
Trust: Damien Neil <dneil@google.com>
Run-TryBot: Damien Neil <dneil@google.com>

…ort multicast loopback

Skip the tests for it, as we already skip them on FreeBSD.

For golang/go#42064
For golang/go#49909

Change-Id: I058f25309020367e686625033b4f25cb614c7f99
Reviewed-on: https://go-review.googlesource.com/c/net/+/366355
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-on: https://go-review.googlesource.com/c/net/+/368534
Trust: Damien Neil <dneil@google.com>
Run-TryBot: Damien Neil <dneil@google.com>

These deadlines were added back in CL 21080043, apparently in an
attempt to increase code coverage numbers. However, nothing in the
tests actually exercises the deadline logic: the tests would pass even
if these methods were no-ops. Their only apparent effect is to make
the tests flaky on slower builders, and to destroy goroutine traces
if the test should ever happen to deadlock.

Updates golang/go#42064
For golang/go#37319

Change-Id: I530a8f3cb80d6d93d1625bc88f0ec7958d4ec35e
Reviewed-on: https://go-review.googlesource.com/c/net/+/366181
Trust: Bryan Mills <bcmills@google.com>
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>