diff --git a/public/sample_ext/Makefile b/public/sample_ext/Makefile
index 537e149c..22ff9208 100644
--- a/public/sample_ext/Makefile
+++ b/public/sample_ext/Makefile
@@ -60,14 +60,10 @@ endif
 BINARY = $(PROJECT).ext.so
 
 OBJ_LINUX := $(OBJECTS:%.cpp=$(BIN_DIR)/%.o)
-OBJ_LINUX := $(OBJECTS:%.c=$(BIN_DIR)/%.o)
 
 $(BIN_DIR)/%.o: %.cpp
 	$(CPP) $(INCLUDE) $(CFLAGS) $(CPPFLAGS) -o $@ -c $<
 
-$(BIN_DIR)/%.o: %.c
-	$(CPP) $(INCLUDE) $(CFLAGS) -o $@ -c $<
-
 all:
 	mkdir -p $(BIN_DIR)
 	ln -sf $(SRCDS)/bin/vstdlib_i486.so vstdlib_i486.so