MD5: avoid casting back and forth between size_t and int

Change-Id: Ia74f41c2bb0dc7b164c7a2920acdedcfe17a2899

MD5.c

@@ -478,11 +478,16 @@ void kwsysMD5_Initialize(kwsysMD5* md5)
 /*--------------------------------------------------------------------------*/
 void kwsysMD5_Append(kwsysMD5* md5, unsigned char const* data, int length)
 {
+  size_t dlen;
   if(length < 0)
     {
-    length = (int)strlen((char const*)data);
+    dlen = strlen((char const*)data);
     }
-  md5_append(&md5->md5_state, (md5_byte_t const*)data, (size_t)length);
+  else
+    {
+    dlen = (size_t)length;
+    }
+  md5_append(&md5->md5_state, (md5_byte_t const*)data, dlen);
 }
 
 /*--------------------------------------------------------------------------*/