diff --git a/include/stdlib.h b/include/stdlib.h
index 4a90831..de63213 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -50,7 +50,7 @@
 #define ROUNDDOWN(a, b) ((a) & ~((b)-1))
 
 /* Macro returns UINT_MAX in case of overflow */
-#define ROUND_TO_PAGE(x,y) (ROUNDUP((x),(y)+1) < (x))?UINT_MAX:ROUNDUP((x),(y)+1)
+#define ROUND_TO_PAGE(x,y) ((ROUNDUP((x),((y)+1)) < (x))?UINT_MAX:ROUNDUP((x),((y)+1)))
 
 /* allocate a buffer on the stack aligned and padded to the cpu's cache line size */
 #define STACKBUF_DMA_ALIGN(var, size) \