#define CACHE_EXT(s) ( (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]) )
#define CACHE_EXT_TREE 0x54524545 /* "TREE" */
-#define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUN" */
+#define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUC" */
struct index_state the_index;