diff options
Diffstat (limited to 'include/ruby/3/attr/maybe_unused.h')
| -rw-r--r-- | include/ruby/3/attr/maybe_unused.h | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/include/ruby/3/attr/maybe_unused.h b/include/ruby/3/attr/maybe_unused.h new file mode 100644 index 0000000000..3463dfb77a --- /dev/null +++ b/include/ruby/3/attr/maybe_unused.h @@ -0,0 +1,40 @@ +/** \noop-*-C++-*-vi:ft=cpp + * @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_MAYBE_UNUSED. + */ +#include "ruby/3/has/attribute.h" +#include "ruby/3/has/c_attribute.h" +#include "ruby/3/has/cpp_attribute.h" + +/** Wraps (or simulates) `[[maybe_unused]]` */ +#if defined(RUBY3_ATTR_MAYBE_UNUSED) +# /* Take that. */ + +#elif RUBY3_HAS_CPP_ATTRIBUTE(maybe_unused) +# define RUBY3_ATTR_MAYBE_UNUSED() [[maybe_unused]] + +#elif RUBY3_HAS_C_ATTRIBUTE(maybe_unused) +# define RUBY3_ATTR_MAYBE_UNUSED() [[maybe_unused]] + +#elif RUBY3_HAS_ATTRIBUTE(unused) +# define RUBY3_ATTR_MAYBE_UNUSED() __attribute__((__unused__)) + +#else +# define RUBY3_ATTR_MAYBE_UNUSED() /* void */ +#endif |