We really have to use double casts to avoid issues with C's and C++'s
signedness propagation rules in implicit casts.
Reported as
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=41178https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=41182
* include/freetype/config/public-macros.h (FT_STATIC_CAST,
FT_REINTERPRET_CAST): Modify macro to take two arguments.
Update all callers.
(FT_STATIC_BYTE_CAST): New macro.
* include/freetype/freetype.h (FT_ENC_TAG): Use `FT_STATIC_BYTE_CAST`.
* include/freetype/ftimage.h (FT_IMAGE_TAG): Ditto.
* include/freetype/fttypes.h (FT_MAKE_TAG): Ditto.
Use `FT_Tag` for casting.
* src/ftraster/ftmisc.h (FT_MAKE_TAG): Removed, no longer needed.
(FT_STATIC_BYTE_CAST): New macro.
* src/smooth/ftgrays.c (FT_STATIC_CAST): Replace with...
(FT_STATIC_BYTE_CAST): ... this.
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.
The following builds were still failing due to previous changes:
make multi
make multi CC="c++"
make CC="c++"
This patch fixes the issues, which were missing includes to get the
right macro definitions in multi-build mode.
Also, `FT_UNUSED' is actually used by third-party code, so move it
back to `public-macros.h' to avoid breaking it.
* include/freetype/config/public-macros.h (FT_EXPORT): Remove
special definition for C++.
(FT_UNUSED): Define here instead of...
* include/freetype/config/compiler-macros.h: ... here.
(FT_FUNCTION_DECLARATION): Remove special definition for C++.
(FT_LOCAL_ARRAY_DEF): Fix definition.
* src/cache/ftccback.h, src/lzw/ftzopen.h, src/gxvalid/gxvmort.h,
src/gxvalid/gxvmorx.h: Add `FT_BEGIN_HEADER' and `FT_END_HEADER'.
* include/freetype/config/public-macros.h
(FT_PUBLIC_FUNCTION_ATTRIBUTE): New macro to tag functions as
public (and thus exportable).
(FT_EXPORT): Use it.
* include/freetype/config/compiler-macros.h
(FT_INTERNAL_FUNCTION_ATTRIBUTE): New macro to tag functions as
internal to the library (and thus hidden). Note that on ELF
systems, all internal functions have hidden visibility, which avoids
the need to enforce this when invoking the compiler (e.g., with an
option like `-fvisibility=hidden').
(FT_FUNCTION_DECLARATION, FT_FUNCTION_DEFINITION): New base macros
to deal with C and C++ linkage issues at the same time.
(FT_LOCAL, FT_LOCAL_DEF, FT_LOCAL_ARRAY, FT_LOCAL_ARRAY_DEF,
FT_BASE, FT_BASE_DEF, FT_EXPORT_VAR, FT_BASE_CALLBACK,
FT_BASE_CALLBACK_DEF): Redefined using new macros.
* builds/unix/ftconfig.h.in, builds/vms/ftconfig.h,
include/freetype/config/ftconfig.h: Split off macro definitions
required by the FreeType API headers to...
* include/freetype/config/public-macros.h: ...this new file.
* builds/unix/ftconfig.h.in, builds/vms/ftconfig.h,
include/freetype/config/ftconfig.h: Split off macro definitions used
by the library but not to be exposed to clients to...
* include/freetype/config/compiler-macros.h: ...this new file.
* include/freetype/internal/*.h, src/raster/ftraster.h: Include
`compiler-macros.h' where needed.
Werner Lemberg