Roll libxml to 2.9.3

third_party/libxml/src/dict.c

 /*
  * dict.c: dictionary of reusable strings, just used to avoid allocation
  *         and freeing operations.
  *
  * Copyright (C) 2003-2012 Daniel Veillard.
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
@@ skipping 468 matching lines @@
                        const xmlChar *name, int len, int seed)
 {
     unsigned long value = (unsigned long) seed;
 
     if (plen == 0)
         value += 30 * (unsigned long) ':';
     else
         value += 30 * (*prefix);
 
     if (len > 10) {
-        value += name[len - (plen + 1 + 1)];
+        int offset = len - (plen + 1 + 1);
+        if (offset < 0)
+            offset = len - (10 + 1);
+        value += name[offset];
         len = 10;
         if (plen > 10)
             plen = 10;
     }
     switch (plen) {
         case 10: value += prefix[9];
         case 9: value += prefix[8];
         case 8: value += prefix[7];
         case 7: value += prefix[6];
         case 6: value += prefix[5];
@@ skipping 750 matching lines @@
     pool = dict->strings;
     while (pool != NULL) {
         limit += pool->size;
         pool = pool->next;
     }
     return(limit);
 }
 
 #define bottom_dict
 #include "elfgcchack.h"