diff --git a/libavcodec/dds.c b/libavcodec/dds.c
index 9e29ada787..9472d86836 100644
--- a/libavcodec/dds.c
+++ b/libavcodec/dds.c
@@ -38,7 +38,7 @@
 
 #define DDPF_FOURCC    (1 <<  2)
 #define DDPF_PALETTE   (1 <<  5)
-#define DDPF_NORMALMAP (1 << 31)
+#define DDPF_NORMALMAP (1U << 31)
 
 enum DDSPostProc {
     DDS_NONE = 0,