fix(runtime): make startup and GTK installation explicit

bench/Makefile

@@ -1,8 +1,9 @@
 CC = cc
-CFLAGS = -Wall -O2
+CFLAGS ?= -O2
 
 bench: main.c ../ipc.c ../ipc.h
-	$(CC) $(CFLAGS) -I.. -o $@ main.c ../ipc.c
+	$(CC) $(CPPFLAGS) -I.. -Wall $(CFLAGS) $(LDFLAGS) -o $@ \
+		main.c ../ipc.c $(LDLIBS)
 
 clean:
 	rm -f bench