Many FreeType clients use C++. However `g++ -Wold-style-cast` warns for
macros with C-style casts even for system header files; this also affects
directories included with `-isystem`. While this could be seen as a problem
with g++, the problem is more a philosophical one: Over the time, C and C++
diverged more and more, and some features of C are no longer the 'right'
solution in C++.
* include/freetype/config/public-macros.h (FT_STATIC_CAST,
FT_REINTERPRET_CAST): New macros.
* include/freetype/freetype.h (FT_ENC_TAG, FT_LOAD_TARGET_,
FT_LOAD_TARGET_MODE): Use `FT_STATIC_CAST`.
Correctly handle negative 'signed char' input.
* include/freetype/ftimage.h (FT_IMAGE_TAG): Ditto.
* include/freetype/fttypes.h (FT_MAKE_TAG, FT_BOOL): Ditto.
* include/freetype/ftmodapi.h (FT_FACE_DRIVER_NAME): Use
`FT_REINTERPRET_CAST`.
* src/smooth/ftgrays.c (FT_STATIC_CAST)[STANDALONE_]: New macro.
[!STANDALONE]: Include `FT_CONFIG_CONFIG_H`.
Fixes#1116.
9079c5d91a