dashboard: only run openbsd-{386,amd64}-62 builders on Go 1.15 and older

For golang/go#42426.

Change-Id: Id8a87ef1952291e06f0076f27ae019bf7ef0e6a2
Reviewed-on: https://go-review.googlesource.com/c/build/+/268880
Trust: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Alexander Rakoczy <alex@golang.org>
diff --git a/dashboard/builders.go b/dashboard/builders.go
index 4f9b014..d7ef5cc 100644
--- a/dashboard/builders.go
+++ b/dashboard/builders.go
@@ -1904,6 +1904,11 @@
 		Name:           "openbsd-386-62",
 		HostType:       "host-openbsd-386-62",
 		distTestAdjust: noTestDirAndNoReboot,
+		buildsRepo: func(repo, branch, goBranch string) bool {
+			// This builder is unfortunately still used by Go 1.15 and 1.14,
+			// so keep it around a bit longer. See golang.org/issue/42426.
+			return atMostGo1(goBranch, 15) && buildRepoByDefault(repo)
+		},
 		env: []string{
 			// cmd/go takes ~192 seconds on openbsd-386
 			// now, which is over the 180 second default
@@ -1913,10 +1918,15 @@
 		},
 	})
 	addBuilder(BuildConfig{
-		Name:              "openbsd-amd64-62",
-		HostType:          "host-openbsd-amd64-62",
-		distTestAdjust:    noTestDirAndNoReboot,
-		tryBot:            nil,
+		Name:           "openbsd-amd64-62",
+		HostType:       "host-openbsd-amd64-62",
+		distTestAdjust: noTestDirAndNoReboot,
+		tryBot:         nil,
+		buildsRepo: func(repo, branch, goBranch string) bool {
+			// This builder is unfortunately still used by Go 1.15 and 1.14,
+			// so keep it around a bit longer. See golang.org/issue/42426.
+			return atMostGo1(goBranch, 15) && buildRepoByDefault(repo)
+		},
 		numTestHelpers:    0,
 		numTryTestHelpers: 5,
 	})
diff --git a/dashboard/builders_test.go b/dashboard/builders_test.go
index 2648b90..9a16981 100644
--- a/dashboard/builders_test.go
+++ b/dashboard/builders_test.go
@@ -396,6 +396,14 @@
 		{b("linux-mips64le-mengzhuo", "sys"), onlyPost},
 		{b("linux-mips64le-mengzhuo", "net"), onlyPost},
 
+		// OpenBSD.
+		{b("openbsd-amd64-64@go1.16", "go"), both},
+		{b("openbsd-amd64-64@go1.15", "go"), both},
+		{b("openbsd-amd64-64@go1.14", "go"), both},
+		{b("openbsd-amd64-62@go1.16", "go"), none}, // golang.org/issue/42426.
+		{b("openbsd-amd64-62@go1.15", "go"), onlyPost},
+		{b("openbsd-amd64-62@go1.14", "go"), onlyPost},
+
 		// go1.12.html: "Go 1.12 is the last release that is
 		// supported on FreeBSD 10.x [... and 11.1]"
 		// But golang.org/issue/40563 happened.