diff --git a/drivers/ddk/stdio/vsprintf.c b/drivers/ddk/stdio/vsprintf.c
index d9cb992d1f..f4857e18f3 100644
--- a/drivers/ddk/stdio/vsprintf.c
+++ b/drivers/ddk/stdio/vsprintf.c
@@ -647,6 +647,8 @@ char *resource_string(char *buf, char *end, struct resource *res,
 #define FLAG_BUF_SIZE		(2 * sizeof(res->flags))
 #define DECODED_BUF_SIZE	sizeof("[mem - 64bit pref window disabled]")
 #define RAW_BUF_SIZE		sizeof("[mem - flags 0x]")
+#undef max
+#define max(a,b) ((a) > (b) ? (a) : (b))
 	char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
 		     2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];