1 files changed, 6 insertions, 3 deletions
diff --git a/src/lib/clog2.c b/src/lib/clog2.c
index 41e2af9791..b9b173177c 100644
--- a/src/lib/clog2.c
+++ b/src/lib/clog2.c
@@ -4,16 +4,19 @@
 #include <console/console.h>
 #endif
 
+/* Assume 8 bits per byte */
+#define CHAR_BIT 8
+
 unsigned long log2(unsigned long x)
 {
         // assume 8 bits per byte.
-        unsigned long i = 1 << (sizeof(x)*8 - 1);
-        unsigned long pow = sizeof(x) * 8 - 1;
+        unsigned long i = 1ULL << (sizeof(x)* CHAR_BIT - 1ULL);
+        unsigned long pow = sizeof(x) * CHAR_BIT - 1ULL;
 
         if (! x) {
 #ifdef DEBUG_LOG2
                 printk_warning("%s called with invalid parameter of 0\n",
-			__FUNCTION__);
+			__func__);
 #endif
                 return -1;
         }