New macros have been created in blead for doing character classification and character case changing of UTF-8 encoded strings. For example, isALPHA_utf8_safe(), toLOWER_utf8_safe(). These take an extra parameter so that the macro can be sure to not read past the end of the string when the UTF-8 is malformed. The existing macros are deprecated, and will raise a warning to that effect on the first use in each call point of a program. Details are in perlapi. Also, handling of some UTF-8 malformations has been changed in the bottom level decode routines. These are unlikely to affect anyone; details are in perldelta, and perlapi.