diff --git a/cpu/6502/Makefile.6502 b/cpu/6502/Makefile.6502
index 59ad3bc07..e043ab9d0 100644
--- a/cpu/6502/Makefile.6502
+++ b/cpu/6502/Makefile.6502
@@ -37,6 +37,8 @@ endif
 
 all: cs8900a.eth lan91c96.eth w5100.eth
 
+.SUFFIXES:
+
 CONTIKI_TARGET_DIRS = . lib sys
 CONTIKI_CPU_DIRS    = . lib sys ctk net
 
diff --git a/cpu/6502/Makefile.customrules-6502 b/cpu/6502/Makefile.customrules-6502
index b2835a1ff..80b22294e 100644
--- a/cpu/6502/Makefile.customrules-6502
+++ b/cpu/6502/Makefile.customrules-6502
@@ -1,5 +1,3 @@
-.SUFFIXES:
-
 CUSTOM_RULE_C_TO_OBJECTDIR_O = 1
 $(OBJECTDIR)/%.o: %.c | $(OBJECTDIR)
 	$(TRACE_CC)