diff --git a/src/build.rules b/src/build.rules
index f1ce7748e..5edfea1df 100644
--- a/src/build.rules
+++ b/src/build.rules
@@ -1,6 +1,9 @@
 .PHONY: all
 all: $(VERIFY) $(ALL) $(EXTRA_TARGETS)
 
+# disable built-in rules
+.SUFFIXES:
+
 ifndef CC
 CC=gcc
 endif