diff --git a/Makefile b/Makefile
index 9b391fd..16c8f20 100644
--- a/Makefile
+++ b/Makefile
@@ -14,12 +14,19 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
+debug = 0
+
 PREFIX = /usr/local
 BINDIR = $(PREFIX)/bin
 
 INSTALL = install -c
 
 CFLAGS += -Wall
+ifeq ($(debug), 1)
+	CFLAGS += -O0 -g
+else
+	CFLAGS += -O2 -DNDEBUG
+endif
 
 SRC := $(wildcard *.c)
 
diff --git a/graftcp-local/main.go b/graftcp-local/main.go
index 7c6f9ec..217914b 100644
--- a/graftcp-local/main.go
+++ b/graftcp-local/main.go
@@ -33,10 +33,7 @@ func (app *App) run() {
 	l := NewLocal(app.ListenAddr, app.Socks5Addr)
 
 	syscall.Mkfifo(app.PipePath, uint32(os.ModePerm))
-	err = os.Chmod(app.PipePath, 0666)
-	if err != nil {
-		dlog.Fatalf("os.Chmod(%s, 0666) err: %s", app.PipePath, err.Error())
-	}
+	os.Chmod(app.PipePath, 0666)
 	l.FifoFd, err = os.OpenFile(app.PipePath, os.O_RDWR, 0)
 	if err != nil {
 		dlog.Fatalf("os.OpenFile(%s) err: %s", app.PipePath, err.Error())