include/freetype/cache/ftcmru.h,
include/freetype/cache/ftcglyph.h,
src/cache/ftcbasic.c,
src/cache/ftccache.c,
src/cache/ftccmap.c,
src/cache/ftcmanag.c:
additional speed optimization to the cache sub-system. It is
now up to 70% faster than the one in the previous table
release (i.e. 2.1.7). Note that the API did slightly change
though.