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Diffstat (limited to 'include/ruby/impl/attr/const.h')
| -rw-r--r-- | include/ruby/impl/attr/const.h | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/include/ruby/impl/attr/const.h b/include/ruby/impl/attr/const.h new file mode 100644 index 0000000000..6c36e9aab2 --- /dev/null +++ b/include/ruby/impl/attr/const.h @@ -0,0 +1,46 @@ +#ifndef RUBY3_ATTR_CONST_H /*-*-C++-*-vi:se ft=cpp:*/ +#define RUBY3_ATTR_CONST_H +/** + * @file + * @author Ruby developers <ruby-core@ruby-lang.org> + * @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 `RUBY3` or `ruby3` 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 Defines #RUBY3_ATTR_CONST. + */ +#include "ruby/3/compiler_since.h" +#include "ruby/3/has/attribute.h" +#include "ruby/3/has/declspec_attribute.h" + +/** Wraps (or simulates) `__attribute__((const))` */ +#if RUBY3_HAS_ATTRIBUTE(const) +# define RUBY3_ATTR_CONST() __attribute__((__const__)) +#elif RUBY3_HAS_DECLSPEC_ATTRIBUTE(noalias) +# /* If a function can be a const, that is also a noalias. */ +# define RUBY3_ATTR_CONST() __declspec(noalias) +#elif RUBY3_COMPILER_SINCE(SunPro, 5, 10, 0) +# define RUBY3_ATTR_CONST() _Pragma("no_side_effect") +#else +# define RUBY3_ATTR_CONST() /* void */ +#endif + +/** Enables #RUBY3_ATTR_CONST iff. #RUBY_NDEBUG. */ +#if RUBY_NDEBUG +# define RUBY3_ATTR_CONST_ON_NDEBUG() RUBY3_ATTR_CONST() +#else +# define RUBY3_ATTR_CONST_ON_NDEBUG() /* void */ +#endif + +#endif /* RUBY3_ATTR_CONST_H */ |