While using zlib in 'solo' mode (via the `Z_SOLO` macro), we actually
include some standard header files, making the typedef fail on systems where
the native `ptrdiff_t` type differs.
Fixes#1124.
* src/zlib/zutil.h: Comment out definition; it doesn't work on Windows.
* src/zlib/patches/freetype-zlib.diff: Updated.
We now first apply zlib's `zlib2ansi` script, then FreeType's patch file.
* src/gzip/README.freetype: Updated.
* patches/0001-zlib-Fix-zlib-sources-to-compile-for-FreeType.patch: Renamed
to...
* patches/freetype-zlib.diff: This.
Clean up description, then regenerate it as follows:
- Copy unmodified files from `zlib` repository.
- Run `zlib2ansi` script.
- Run `git diff -R > patches/freetype-zlib.diff.new`.
- Insert patch description of old diff file, then replace old diff with
new diff file.
Werner Lemberg