diff --git a/libavutil/Makefile b/libavutil/Makefile
index a2e35e708c..8155d5acb0 100644
--- a/libavutil/Makefile
+++ b/libavutil/Makefile
@@ -3,8 +3,6 @@
 #
 include ../config.mak
 
-CFLAGS+=-DBUILD_AVUTIL
-
 OBJS= mathematics.o \
       rational.o \
       intfloat_readwrite.o \