diff --git a/aom_ports/x86.h b/aom_ports/x86.h
index 79cbd02..f390dfa 100644
--- a/aom_ports/x86.h
+++ b/aom_ports/x86.h
@@ -387,7 +387,7 @@
   // Reserved                      01B
   // Double Precision (53-Bits)    10B
   // Extended Precision (64-Bits)  11B
-  x87_set_control_word((mode & ~0x300) | 0x200);
+  x87_set_control_word((mode & ~0x300u) | 0x200u);
   return mode;
 }