diff --git a/vp8/common/blockd.h b/vp8/common/blockd.h
index 75dd4f79d2af409a13c48b3196bf734af4c7ab48..db8400ae4f4c7c4ca9a334d83111fb33aa7781d6 100644
--- a/vp8/common/blockd.h
+++ b/vp8/common/blockd.h
@@ -169,7 +169,7 @@ typedef struct
         MV  as_mv;
     } mv;
 
-    char partitioning;
+    unsigned char partitioning;
     unsigned char mb_skip_coeff;                                //does this mb has coefficients at all, 1=no coefficients, 0=need decode tokens
     unsigned char dc_diff;
     unsigned char need_to_clamp_mvs;