syz-ci: use gmake instead of make on openbsd

Update google#712

pkg/instance/instance.go

@@ -12,6 +12,7 @@ import (
 	"net"
 	"os"
 	"path/filepath"
+	"runtime"
 	"strings"
 	"time"
 
@@ -61,7 +62,7 @@ func (env *Env) BuildSyzkaller(repo, commit string) error {
 	if _, err := vcs.NewSyzkallerRepo(cfg.Syzkaller).CheckoutCommit(repo, commit); err != nil {
 		return fmt.Errorf("failed to checkout syzkaller repo: %v", err)
 	}
-	cmd := osutil.Command("make", "target")
+	cmd := osutil.Command(MakeBin, "target")
 	cmd.Dir = cfg.Syzkaller
 	cmd.Env = append([]string{}, os.Environ()...)
 	cmd.Env = append(cmd.Env,
@@ -397,3 +398,10 @@ func ExecprogCmd(execprog, executor, OS, arch, sandbox string, repeat, threaded,
 		procs, repeatCount, threaded, collide,
 		faultCall, faultNth, progFile)
 }
+
+var MakeBin = func() string {
+	if runtime.GOOS == "openbsd" {
+		return "gmake"
+	}
+	return "make"
+}()

syz-ci/syzupdater.go

@@ -12,6 +12,7 @@ import (
 	"syscall"
 	"time"
 
+	"github.com/google/syzkaller/pkg/instance"
 	"github.com/google/syzkaller/pkg/log"
 	"github.com/google/syzkaller/pkg/mgrconfig"
 	"github.com/google/syzkaller/pkg/osutil"
@@ -218,21 +219,21 @@ func (upd *SyzUpdater) build(commit *vcs.Commit) error {
 			}
 		}
 	}
-	cmd := osutil.Command("make", "generate")
+	cmd := osutil.Command(instance.MakeBin, "generate")
 	cmd.Dir = upd.syzkallerDir
 	cmd.Env = append([]string{"GOPATH=" + upd.gopathDir}, os.Environ()...)
 	if _, err := osutil.Run(time.Hour, cmd); err != nil {
 		return fmt.Errorf("build failed: %v", err)
 	}
-	cmd = osutil.Command("make", "host", "ci")
+	cmd = osutil.Command(instance.MakeBin, "host", "ci")
 	cmd.Dir = upd.syzkallerDir
 	cmd.Env = append([]string{"GOPATH=" + upd.gopathDir}, os.Environ()...)
 	if _, err := osutil.Run(time.Hour, cmd); err != nil {
 		return fmt.Errorf("build failed: %v", err)
 	}
 	for target := range upd.targets {
 		parts := strings.Split(target, "/")
-		cmd = osutil.Command("make", "target")
+		cmd = osutil.Command(instance.MakeBin, "target")
 		cmd.Dir = upd.syzkallerDir
 		cmd.Env = append([]string{}, os.Environ()...)
 		cmd.Env = append(cmd.Env,