diff --git a/3rdParty/LibIDN/src/stringprep.c b/3rdParty/LibIDN/src/stringprep.c
old mode 100644
new mode 100755
index 8ff28e6..19bf0d9
--- a/3rdParty/LibIDN/src/stringprep.c
+++ b/3rdParty/LibIDN/src/stringprep.c
@@ -33,6 +33,7 @@
 
 #include <stdlib.h>
 #include <string.h>
+#include <assert.h>
 
 #include "stringprep.h"
 
@@ -372,7 +373,7 @@ stringprep (char *in,
   int rc;
   char *utf8 = NULL;
   uint32_t *ucs4 = NULL;
-  size_t ucs4len, maxucs4len, adducs4len = 50;
+  size_t ucs4len = SIZE_MAX, maxucs4len = SIZE_MAX, adducs4len = 50;
 
   do
     {
@@ -380,8 +381,10 @@ stringprep (char *in,
 
       free (ucs4);
       ucs4 = stringprep_utf8_to_ucs4 (in, -1, &ucs4len);
-      if (ucs4 == NULL)
-	return STRINGPREP_ICONV_ERROR;
+	  if (ucs4 == NULL) {
+		  return STRINGPREP_ICONV_ERROR;
+	  }
+	  assert(ucs4len != SIZE_MAX);
       maxucs4len = ucs4len + adducs4len;
       newp = realloc (ucs4, maxucs4len * sizeof (uint32_t));
       if (!newp)