diff options
| author | 卜部昌平 <[email protected]> | 2024-04-25 09:25:15 +0200 |
|---|---|---|
| committer | 卜部昌平 <[email protected]> | 2024-04-27 21:55:28 +0900 |
| commit | bb5a53820703f5e1af886a0c5ca7178aa976be29 (patch) | |
| tree | 4e7d416e1c1811cad81e0c7e73db8fde722875b5 /include/ruby/internal/stdckdint.h | |
| parent | 9ea77cb3514664fc150515765fb9ede5b2b6ab4c (diff) | |
use of stdckdint.h
C23 is going to have this header. The industry is already moving
towards accepting it; OSes and compilers started to implement theirs.
Why not detect its presence and if any, prefer over other ways.
See also:
- https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2683.pdf
- https://reviews.freebsd.org/D41734
- https://reviews.llvm.org/D157331
- https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=8441841a1b985d68245954af1ff023db121b0635
Diffstat (limited to 'include/ruby/internal/stdckdint.h')
| -rw-r--r-- | include/ruby/internal/stdckdint.h | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/include/ruby/internal/stdckdint.h b/include/ruby/internal/stdckdint.h new file mode 100644 index 0000000000..d02530136e --- /dev/null +++ b/include/ruby/internal/stdckdint.h @@ -0,0 +1,60 @@ +#ifndef RBIMPL_STDCKDINT_H /*-*-C++-*-vi:se ft=cpp:*/ +#define RBIMPL_STDCKDINT_H +/** + * @author Ruby developers <[email protected]> + * @copyright This file is a part of the programming language Ruby. + * Permission is hereby granted, to either redistribute and/or + * modify this file, provided that the conditions mentioned in the + * file COPYING are met. Consult the file for details. + * @warning Symbols prefixed with either `RBIMPL` or `rbimpl` are + * implementation details. Don't take them as canon. They could + * rapidly appear then vanish. The name (path) of this header file + * is also an implementation detail. Do not expect it to persist + * at the place it is now. Developers are free to move it anywhere + * anytime at will. + * @note To ruby-core: remember that this header can be possibly + * recursively included from extension libraries written in C++. + * Do not expect for instance `__VA_ARGS__` is always available. + * We assume C99 for ruby itself but we don't assume languages of + * extension libraries. They could be written in C++98. + * @brief C23 shim for <stdckdint.h> + */ +#include "ruby/internal/config.h" +#include "ruby/internal/has/builtin.h" +#include "ruby/internal/stdbool.h" + +#ifdef __has_include +# if __has_include(<stdckdint.h>) +# /* Conforming C23 situation; e.g. recent clang */ +# define RBIMPL_HAVE_STDCKDINT_H +# endif +#endif + +#ifdef HAVE_STDCKDINT_H +# /* Some OSes (most notably FreeBSD) have this file. */ +# define RBIMPL_HAVE_STDCKDINT_H +#endif + +#ifdef RBIMPL_HAVE_STDCKDINT_H +# /* Take that. */ +# include <stdckdint.h> + +#elif RBIMPL_HAS_BUILTIN(__builtin_add_overflow) +# define ckd_add(x, y, z) ((bool)__builtin_add_overflow((y), (z), (x))) +# define ckd_sub(x, y, z) ((bool)__builtin_sub_overflow((y), (z), (x))) +# define ckd_mul(x, y, z) ((bool)__builtin_mul_overflow((y), (z), (x))) +# define __STDC_VERSION_STDCKDINT_H__ 202311L + +#/* elif defined(__cplusplus) */ +#/* :TODO: if we assume C++11 we can use `<type_traits>` to implement them. */ + +#else +# /* intentionally leave them undefined */ +# /* to make `#ifdef ckd_add` etc. work as intended. */ +# undef ckd_add +# undef ckd_sub +# undef ckd_mul +# undef __STDC_VERSION_STDCKDINT_H__ +#endif + +#endif /* RBIMPL_STDCKDINT_H */ |