Fix cast-align warnings - Suppress warnings in xmlmemory.c by casting to 'void *'. - Remove unneeded cast in xmlschemas.c that caused a macro precedence error. - Add dummy fields to short structs in xmlschemas.c. This increases the size of the structs, but I can't see a better solution without using C11's _Alignof operator. There are still a couple of cast-align warnings in encoding.c. These are legitimate portability issues that can't be fixed without reworking the conversion functions.