mv include/ruby/{3,impl}

Devs do not love "3".

24 files changed, 0 insertions, 1062 deletions

diff --git a/include/ruby/3/attr/alloc_size.h b/include/ruby/3/attr/alloc_size.h
deleted file mode 100644
index 5d4ece08a1..0000000000
--- a/include/ruby/3/attr/alloc_size.h
+++ /dev/null
@@ -1,32 +0,0 @@
-#ifndef RUBY3_ATTR_ALLOC_SIZE_H                      /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_ALLOC_SIZE_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_ALLOC_SIZE.
- */
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((alloc_size))` */
-#if RUBY3_HAS_ATTRIBUTE(alloc_size)
-# define RUBY3_ATTR_ALLOC_SIZE(tuple) __attribute__((__alloc_size__ tuple))
-#else
-# define RUBY3_ATTR_ALLOC_SIZE(tuple) /* void */
-#endif
-
-#endif /* RUBY3_ATTR_ALLOC_SIZE_H */
diff --git a/include/ruby/3/attr/artificial.h b/include/ruby/3/attr/artificial.h
deleted file mode 100644
index f5450e3467..0000000000
--- a/include/ruby/3/attr/artificial.h
+++ /dev/null
@@ -1,46 +0,0 @@
-#ifndef RUBY3_ATTR_ARTIFICIAL_H                      /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_ARTIFICIAL_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_ARTIFICIAL.
- *
- * ### Q&A ###
- *
- * - Q: What is this attribute?  I don't get what GCC manual is talking about.
- *
- * - A: In  short  it  is  an  attribute to  manipulate  GDB  backtraces.   The
- *      attribute    makes    the   best    sense    when    it   comes    with
- *      __attribute__((always_inline)).   When a  function annotated  with this
- *      attribute gets inlined, and when you  somehow look at a backtrace which
- *      includes such  inlined call site,  then the backtrace shows  the caller
- *      and  not the  callee.  This  is handy  for instance  when an  identical
- *      function is inlined  more than once in a single  big function.  On such
- *      case it gets  vital to know where the inlining  happened in the callee.
- *      See also https://stackoverflow.com/a/21936099
- */
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((artificial))` */
-#if RUBY3_HAS_ATTRIBUTE(artificial)
-# define RUBY3_ATTR_ARTIFICIAL() __attribute__((__artificial__))
-#else
-# define RUBY3_ATTR_ARTIFICIAL() /* void */
-#endif
-
-#endif /* RUBY3_ATTR_ARTIFICIAL_H */
diff --git a/include/ruby/3/attr/cold.h b/include/ruby/3/attr/cold.h
deleted file mode 100644
index 3822f0a975..0000000000
--- a/include/ruby/3/attr/cold.h
+++ /dev/null
@@ -1,37 +0,0 @@
-#ifndef RUBY3_ATTR_COLD_H                            /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_COLD_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_COLD.
- */
-#include "ruby/3/compiler_is.h"
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((cold))` */
-#if RUBY3_COMPILER_IS(SunPro)
-# /* Recent SunPro has __has_attribute, and is borken. */
-# /* It reports it has attribute cold, reality isn't (warnings issued). */
-# define RUBY3_ATTR_COLD() /* void */
-#elif RUBY3_HAS_ATTRIBUTE(cold)
-# define RUBY3_ATTR_COLD() __attribute__((__cold__))
-#else
-# define RUBY3_ATTR_COLD() /* void */
-#endif
-
-#endif /* RUBY3_ATTR_COLD_H */
diff --git a/include/ruby/3/attr/const.h b/include/ruby/3/attr/const.h
deleted file mode 100644
index 6c36e9aab2..0000000000
--- a/include/ruby/3/attr/const.h
+++ /dev/null
@@ -1,46 +0,0 @@
-#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 */
diff --git a/include/ruby/3/attr/constexpr.h b/include/ruby/3/attr/constexpr.h
deleted file mode 100644
index 576ec7fb8f..0000000000
--- a/include/ruby/3/attr/constexpr.h
+++ /dev/null
@@ -1,85 +0,0 @@
-#ifndef RUBY3_ATTR_CONSTEXPR_H                       /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_CONSTEXPR_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      #RUBY3_ATTR_CONSTEXPR.
- */
-#include "ruby/3/has/feature.h"
-#include "ruby/3/compiler_is.h"
-#include "ruby/3/token_paste.h"
-
-/** @cond INTERNAL_MACRO */
-#if ! defined(__cplusplus)
-# /* Makes no sense. */
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX11 0
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX14 0
-
-#elif defined(__cpp_constexpr)
-# /* https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations */
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX11 (__cpp_constexpr >= 200704L)
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX14 (__cpp_constexpr >= 201304L)
-
-#elif RUBY3_COMPILER_SINCE(MSVC, 19, 0, 0)
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX11 RUBY3_COMPILER_SINCE(MSVC, 19, 00, 00)
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX14 RUBY3_COMPILER_SINCE(MSVC, 19, 11, 00)
-
-#elif RUBY3_COMPILER_SINCE(SunPro, 5, 13, 0)
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX11 (__cplusplus >= 201103L)
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX14 (__cplusplus >= 201402L)
-
-#elif RUBY3_COMPILER_SINCE(GCC, 4, 9, 0)
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX11 (__cplusplus >= 201103L)
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX14 (__cplusplus >= 201402L)
-
-#elif RUBY3_HAS_FEATURE(cxx_relaxed_constexpr)
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX11 1
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX14 1
-
-#elif RUBY3_HAS_FEATURE(cxx_constexpr)
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX11 1
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX14 0
-
-#else
-# /* :FIXME: icpc must have constexpr but don't know how to detect. */
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX11 0
-# define RUBY3_HAS_ATTR_CONSTEXPR_CXX14 0
-#endif
-/** @endcond */
-
-/** Wraps (or simulates) C++11 `constexpr`.  */
-#if RUBY3_HAS_ATTR_CONSTEXPR_CXX14
-# define RUBY3_ATTR_CONSTEXPR(_) constexpr
-
-#elif RUBY3_HAS_ATTR_CONSTEXPR_CXX11
-# define RUBY3_ATTR_CONSTEXPR(_) RUBY3_TOKEN_PASTE(RUBY3_ATTR_CONSTEXPR_, _)
-# define RUBY3_ATTR_CONSTEXPR_CXX11 constexpr
-# define RUBY3_ATTR_CONSTEXPR_CXX14 /* void */
-
-#else
-# define RUBY3_ATTR_CONSTEXPR(_) /* void */
-#endif
-
-/** Enables #RUBY3_ATTR_CONSTEXPR iff. #RUBY_NDEBUG. */
-#if RUBY_NDEBUG
-# define RUBY3_ATTR_CONSTEXPR_ON_NDEBUG(_) RUBY3_ATTR_CONSTEXPR(_)
-#else
-# define RUBY3_ATTR_CONSTEXPR_ON_NDEBUG(_) /* void */
-#endif
-
-#endif /* RUBY3_ATTR_CONSTEXPR_H */
diff --git a/include/ruby/3/attr/deprecated.h b/include/ruby/3/attr/deprecated.h
deleted file mode 100644
index 5c3f508ffc..0000000000
--- a/include/ruby/3/attr/deprecated.h
+++ /dev/null
@@ -1,59 +0,0 @@
-#ifndef RUBY3_ATTR_DEPRECATED_H                      /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_DEPRECATED_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_DEPRECATED.
- */
-#include "ruby/3/compiler_since.h"
-#include "ruby/3/has/attribute.h"
-#include "ruby/3/has/c_attribute.h"
-#include "ruby/3/has/cpp_attribute.h"
-#include "ruby/3/has/declspec_attribute.h"
-#include "ruby/3/has/extension.h"
-
-/** Wraps (or simulates) `[[deprecated]]` */
-#if RUBY3_HAS_EXTENSION(attribute_deprecated_with_message)
-# define RUBY3_ATTR_DEPRECATED(msg) __attribute__((__deprecated__ msg))
-
-#elif RUBY3_COMPILER_SINCE(GCC, 4, 5, 0)
-# define RUBY3_ATTR_DEPRECATED(msg) __attribute__((__deprecated__ msg))
-
-#elif RUBY3_COMPILER_SINCE(Intel, 13, 0, 0)
-# define RUBY3_ATTR_DEPRECATED(msg) __attribute__((__deprecated__ msg))
-
-#elif RUBY3_HAS_ATTRIBUTE(deprecated) /* but not with message. */
-# define RUBY3_ATTR_DEPRECATED(msg) __attribute__((__deprecated__))
-
-#elif RUBY3_COMPILER_SINCE(MSVC, 14, 0, 0)
-# define RUBY3_ATTR_DEPRECATED(msg) __declspec(deprecated msg)
-
-#elif RUBY3_HAS_DECLSPEC_ATTRIBUTE(deprecated)
-# define RUBY3_ATTR_DEPRECATED(msg) __declspec(deprecated)
-
-#elif RUBY3_HAS_CPP_ATTRIBUTE(deprecated)
-# define RUBY3_ATTR_DEPRECATED(msg) [[deprecated msg]]
-
-#elif RUBY3_HAS_C_ATTRIBUTE(deprecated)
-# define RUBY3_ATTR_DEPRECATED(msg) [[deprecated msg]]
-
-#else
-# define RUBY3_ATTR_DEPRECATED(msg) /* void */
-#endif
-
-#endif /* RUBY3_ATTR_DEPRECATED_H */
diff --git a/include/ruby/3/attr/diagnose_if.h b/include/ruby/3/attr/diagnose_if.h
deleted file mode 100644
index 2f09abc94d..0000000000
--- a/include/ruby/3/attr/diagnose_if.h
+++ /dev/null
@@ -1,42 +0,0 @@
-#ifndef RUBY3_ATTR_DIAGNOSE_IF_H                     /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_DIAGNOSE_IF_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_DIAGNOSE_IF.
- */
-#include "ruby/3/has/attribute.h"
-#include "ruby/3/warning_push.h"
-
-/** Wraps (or simulates) `__attribute__((diagnose_if))` */
-#if RUBY3_COMPILER_BEFORE(Clang, 5, 0, 0)
-# /* https://bugs.llvm.org/show_bug.cgi?id=34319 */
-# define RUBY3_ATTR_DIAGNOSE_IF(_, __, ___) /* void */
-
-#elif RUBY3_HAS_ATTRIBUTE(diagnose_if)
-# define RUBY3_ATTR_DIAGNOSE_IF(_, __, ___) \
-    RUBY3_WARNING_PUSH() \
-    RUBY3_WARNING_IGNORED(-Wgcc-compat) \
-    __attribute__((__diagnose_if__(_, __, ___))) \
-    RUBY3_WARNING_POP()
-
-#else
-# define RUBY3_ATTR_DIAGNOSE_IF(_, __, ___) /* void */
-#endif
-
-#endif /* RUBY3_ATTR_DIAGNOSE_IF_H */
diff --git a/include/ruby/3/attr/enum_extensibility.h b/include/ruby/3/attr/enum_extensibility.h
deleted file mode 100644
index 15a5b063f2..0000000000
--- a/include/ruby/3/attr/enum_extensibility.h
+++ /dev/null
@@ -1,32 +0,0 @@
-#ifndef RUBY3_ATTR_ENUM_EXTENSIBILITY_H              /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_ENUM_EXTENSIBILITY_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      #RUBY3_ATTR_ENUM_EXTENSIBILITY.
- */
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((enum_extensibility))` */
-#if RUBY3_HAS_ATTRIBUTE(enum_extensibility)
-# define RUBY3_ATTR_ENUM_EXTENSIBILITY(_) __attribute__((__enum_extensibility__(_)))
-#else
-# define RUBY3_ATTR_ENUM_EXTENSIBILITY(_) /* void */
-#endif
-
-#endif /* RUBY3_ATTR_ENUM_EXTENSIBILITY_H */
diff --git a/include/ruby/3/attr/error.h b/include/ruby/3/attr/error.h
deleted file mode 100644
index 53628259a0..0000000000
--- a/include/ruby/3/attr/error.h
+++ /dev/null
@@ -1,32 +0,0 @@
-#ifndef RUBY3_ATTR_ERROR_H                           /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_ERROR_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_ERROR.
- */
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((error))` */
-#if RUBY3_HAS_ATTRIBUTE(error)
-# define RUBY3_ATTR_ERROR(msg) __attribute__((__error__ msg))
-#else
-# define RUBY3_ATTR_ERROR(msg) /* void */
-#endif
-
-#endif /* RUBY3_ATTR_ERROR_H */
diff --git a/include/ruby/3/attr/flag_enum.h b/include/ruby/3/attr/flag_enum.h
deleted file mode 100644
index 2081c9c3ed..0000000000
--- a/include/ruby/3/attr/flag_enum.h
+++ /dev/null
@@ -1,33 +0,0 @@
-#ifndef RUBY3_ATTR_FLAG_ENUM_H                       /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_FLAG_ENUM_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_FLAG_ENUM.
- * @see        https://clang.llvm.org/docs/AttributeReference.html#flag_enum
- */
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((flag_enum)` */
-#if RUBY3_HAS_ATTRIBUTE(flag_enum)
-# define RUBY3_ATTR_FLAG_ENUM() __attribute__((__flag_enum__))
-#else
-# define RUBY3_ATTR_FLAG_ENUM() /* void */
-#endif
-
-#endif /* RUBY3ATTR_FLAG_ENUM_H */
diff --git a/include/ruby/3/attr/forceinline.h b/include/ruby/3/attr/forceinline.h
deleted file mode 100644
index bd622eddce..0000000000
--- a/include/ruby/3/attr/forceinline.h
+++ /dev/null
@@ -1,40 +0,0 @@
-#ifndef RUBY3_ATTR_FORCEINLINE_H                     /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_FORCEINLINE_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_FORCEINLINE.
- */
-#include "ruby/3/compiler_since.h"
-#include "ruby/3/has/attribute.h"
-
-/**
- * Wraps (or  simulates) `__forceinline`.  MSVC complains  on declarations like
- * `static inline __forceinline void foo()`.   It  seems  MSVC's  `inline`  and
- * `__forceinline` are mutually exclusive.  We have to mimic that behaviour for
- * non-MSVC compilers.
- */
-#if RUBY3_COMPILER_SINCE(MSVC, 12, 0, 0)
-# define RUBY3_ATTR_FORCEINLINE() __forceinline
-#elif RUBY3_HAS_ATTRIBUTE(always_inline)
-# define RUBY3_ATTR_FORCEINLINE() __attribute__((__always_inline__)) inline
-#else
-# define RUBY3_ATTR_FORCEINLINE() inline
-#endif
-
-#endif /* RUBY3_ATTR_FORCEINLINE_H */
diff --git a/include/ruby/3/attr/format.h b/include/ruby/3/attr/format.h
deleted file mode 100644
index 2624179bda..0000000000
--- a/include/ruby/3/attr/format.h
+++ /dev/null
@@ -1,38 +0,0 @@
-#ifndef RUBY3_ATTR_FORMAT_H                          /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_FORMAT_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_FORMAT.
- */
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((format))` */
-#if RUBY3_HAS_ATTRIBUTE(format)
-# define RUBY3_ATTR_FORMAT(x, y, z) __attribute__((__format__(x, y, z)))
-#else
-# define RUBY3_ATTR_FORMAT(x, y, z) /* void */
-#endif
-
-#if defined(__MINGW_PRINTF_FORMAT)
-# define RUBY3_PRINTF_FORMAT __MINGW_PRINTF_FORMAT
-#else
-# define RUBY3_PRINTF_FORMAT __printf__
-#endif
-
-#endif /* RUBY3_ATTR_FORMAT_H */
diff --git a/include/ruby/3/attr/maybe_unused.h b/include/ruby/3/attr/maybe_unused.h
deleted file mode 100644
index 71904dffa4..0000000000
--- a/include/ruby/3/attr/maybe_unused.h
+++ /dev/null
@@ -1,38 +0,0 @@
-#ifndef RUBY3_ATTR_MAYBE_UNUSED_H                    /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_MAYBE_UNUSED_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_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 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
-
-#endif /* RUBY3_ATTR_MAYBE_UNUSED */
diff --git a/include/ruby/3/attr/noalias.h b/include/ruby/3/attr/noalias.h
deleted file mode 100644
index 49ad11999d..0000000000
--- a/include/ruby/3/attr/noalias.h
+++ /dev/null
@@ -1,58 +0,0 @@
-#ifndef RUBY3_ATTR_NOALIAS_H                         /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_NOALIAS_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_NOALIAS.
- *
- * ### Q&A ###
- *
- * - Q: There  are   seemingly  similar  attributes   named  #RUBY3_ATTR_CONST,
- *      #RUBY3_ATTR_PURE, and #RUBY3_ATTR_NOALIAS.  What are the difference?
- *
- * - A: Allowed operations are different.
- *
- *     - #RUBY3_ATTR_CONST ... Functions attributed by  this are not allowed to
- *       read/write  _any_ pointers  at all  (there are  exceptional situations
- *       when  reading a  pointer is  possible but  forget that;  they are  too
- *       exceptional  to be  useful).  Just  remember that  everything pointer-
- *       related are NG.
- *
- *     - #RUBY3_ATTR_PURE  ...   Functions  attributed  by this  can  read  any
- *       nonvolatile pointers, but  no writes are allowed at  all.  The ability
- *       to read _any_ nonvolatile pointers  makes it possible to mark ::VALUE-
- *       taking functions as being pure, as long as they are read-only.
- *
- *     - #RUBY3_ATTR_NOALIAS ... Can both read/write, but only through pointers
- *       passed to  the function  as parameters.  This  is a  typical situation
- *       when you create  a C++ non-static member function  which only concerns
- *       `this`.  No  global variables are  allowed to read/write.  So  this is
- *       not a  super-set of being pure.   If you want to  read something, that
- *       has  to be  passed  to the  function as  a  pointer.  ::VALUE  -taking
- *       functions thus cannot be attributed as such.
- */
-#include "ruby/3/has/declspec_attribute.h"
-
-/** Wraps (or simulates) `__declspec((noalias))` */
-#if RUBY3_HAS_DECLSPEC_ATTRIBUTE(noalias)
-# define RUBY3_ATTR_NOALIAS() __declspec(noalias)
-#else
-# define RUBY3_ATTR_NOALIAS() /* void */
-#endif
-
-#endif /* RUBY3_ATTR_NOALIAS_H */
diff --git a/include/ruby/3/attr/nodiscard.h b/include/ruby/3/attr/nodiscard.h
deleted file mode 100644
index 6168bb9002..0000000000
--- a/include/ruby/3/attr/nodiscard.h
+++ /dev/null
@@ -1,45 +0,0 @@
-#ifndef RUBY3_ATTR_NODISCARD_H                       /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_NODISCARD_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_NODISCARD.
- */
-#include "ruby/3/has/attribute.h"
-#include "ruby/3/has/c_attribute.h"
-#include "ruby/3/has/cpp_attribute.h"
-
-/**
- * Wraps  (or simulates)  `[[nodiscard]]`.  In  C++  (at least  since C++20)  a
- * nodiscard attribute can  have a message why the result  shall not be ignoed.
- * However GCC attribute and SAL annotation cannot take them.
- */
-#if RUBY3_HAS_CPP_ATTRIBUTE(nodiscard)
-# define RUBY3_ATTR_NODISCARD() [[nodiscard]]
-#elif RUBY3_HAS_C_ATTRIBUTE(nodiscard)
-# define RUBY3_ATTR_NODISCARD() [[nodiscard]]
-#elif RUBY3_HAS_ATTRIBUTE(warn_unused_result)
-# define RUBY3_ATTR_NODISCARD() __attribute__((__warn_unused_result__))
-#elif defined(_Check_return_)
-# /* Take SAL definition. */
-# define RUBY3_ATTR_NODISCARD() _Check_return_
-#else
-# define RUBY3_ATTR_NODISCARD() /* void */
-#endif
-
-#endif /* RUBY3_ATTR_NODISCARD_H */
diff --git a/include/ruby/3/attr/noexcept.h b/include/ruby/3/attr/noexcept.h
deleted file mode 100644
index aff3b2cb1b..0000000000
--- a/include/ruby/3/attr/noexcept.h
+++ /dev/null
@@ -1,91 +0,0 @@
-#ifndef RUBY3_ATTR_NOEXCEPT_H                       /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_NOEXCEPT_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_NOEXCEPT.
- *
- * This isn't actually an attribute in C++ but who cares...
- *
- * Mainly due  to aesthetic reasons,  this one is  rarely used in  the project.
- * But can  be handy on  occasions, especially when a  function's noexcept-ness
- * depends on its calling functions.
- *
- * ### Q&A ###
- *
- * - Q: Can a function that raises Ruby exceptions be attributed `noexcept`?
- *
- * - A: Yes.   `noexcept` is  about  C++ exceptions,  not  Ruby's.  They  don't
- *      interface each other.  You can  safely attribute a function that raises
- *      Ruby exceptions as `noexcept`.
- *
- * - Q: How, then, can I assert that  a function I wrote doesn't raise any Ruby
- *      exceptions?
- *
- * - A: `__attribute__((__leaf__))` is for that purpose.  A function attributed
- *      as leaf can still throw C++  exceptions, but not Ruby's.  Note however,
- *      that it's extremely difficult -- if  not impossible -- to assert that a
- *      function  doesn't  raise any  Ruby  exceptions  at  all.  Use  of  that
- *      attribute is not  recommended; mere mortals can't properly  use that by
- *      hand.
- *
- * - Q: Does it make sense to attribute an inline function `noexcept`?
- *
- * - A: I thought so before.  But no, I don't think they are useful any longer.
- *
- *     - When an  inline function attributed `noexcept`  actually doesn't throw
- *       any  exceptions at  all:  these days  I don't  see  any difference  in
- *       generated assembly  by adding/removing this attribute.   C++ compilers
- *       get smarter and  smarter.  Today they can infer if  it actually throws
- *       or not without any annotations by humans (correct me if I'm wrong).
- *
- *     - When an inline function attributed `noexcepr` actually _does_ throw an
- *       exception:  they  have to  call  `std::terminate`  then (C++  standard
- *       mandates  so).  This  means exception  handling routines  are actually
- *       enforced, not  omitted.  This doesn't impact  runtime performance (The
- *       Itanium C++ ABI has zero-cost  exception handling), but does impact on
- *       generated binary size.  This is bad.
- */
-#include "ruby/3/compiler_since.h"
-#include "ruby/3/has/feature.h"
-
-/** Wraps (or simulates) C++11 `noexcept` */
-#if ! defined(__cplusplus)
-# /* Doesn't make sense. */
-# define RUBY3_ATTR_NOEXCEPT(_) /* void */
-
-#elif RUBY3_HAS_FEATURE(cxx_noexcept)
-# define RUBY3_ATTR_NOEXCEPT(_) noexcept(noexcept(_))
-
-#elif defined(__GXX_EXPERIMENTAL_CXX0X__) && __GXX_EXPERIMENTAL_CXX0X__
-# define RUBY3_ATTR_NOEXCEPT(_) noexcept(noexcept(_))
-
-#elif defined(__INTEL_CXX11_MODE__)
-# define RUBY3_ATTR_NOEXCEPT(_) noexcept(noexcept(_))
-
-#elif RUBY3_COMPILER_SINCE(MSVC, 19, 0, 0)
-# define RUBY3_ATTR_NOEXCEPT(_) noexcept(noexcept(_))
-
-#elif __cplusplus >= 201103L
-# define RUBY3_ATTR_NOEXCEPT(_) noexcept(noexcept(_))
-
-#else
-# define RUBY3_ATTR_NOEXCEPT(_) /* void */
-#endif
-
-#endif /* RUBY3_ATTR_NOEXCEPT_H */
diff --git a/include/ruby/3/attr/noinline.h b/include/ruby/3/attr/noinline.h
deleted file mode 100644
index 4437f8a32f..0000000000
--- a/include/ruby/3/attr/noinline.h
+++ /dev/null
@@ -1,35 +0,0 @@
-#ifndef RUBY3_ATTR_NOINLINE_H                        /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_NOINLINE_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_NOINLINE.
- */
-#include "ruby/3/has/attribute.h"
-#include "ruby/3/has/declspec_attribute.h"
-
-/** Wraps (or simulates) `__declspec(noinline)` */
-#if RUBY3_HAS_DECLSPEC_ATTRIBUTE(noinline)
-# define RUBY3_ATTR_NOINLINE() __declspec(noinline)
-#elif RUBY3_HAS_ATTRIBUTE(noinline)
-# define RUBY3_ATTR_NOINLINE() __attribute__((__noinline__))
-#else
-# define RUBY3_ATTR_NOINLINE() /* void */
-#endif
-
-#endif /* RUBY3_ATTR_NOINLINE_H */
diff --git a/include/ruby/3/attr/nonnull.h b/include/ruby/3/attr/nonnull.h
deleted file mode 100644
index 01b5820c1b..0000000000
--- a/include/ruby/3/attr/nonnull.h
+++ /dev/null
@@ -1,32 +0,0 @@
-#ifndef RUBY3_ATTR_NONNULL_H                         /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_NONNULL_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_NONNULL.
- */
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((nonnull))` */
-#if RUBY3_HAS_ATTRIBUTE(nonnull)
-# define RUBY3_ATTR_NONNULL(list) __attribute__((__nonnull__ list))
-#else
-# define RUBY3_ATTR_NONNULL(list) /* void */
-#endif
-
-#endif /* RUBY3_ATTR_NONNULL_H */
diff --git a/include/ruby/3/attr/noreturn.h b/include/ruby/3/attr/noreturn.h
deleted file mode 100644
index 999a76b8e5..0000000000
--- a/include/ruby/3/attr/noreturn.h
+++ /dev/null
@@ -1,52 +0,0 @@
-#ifndef RUBY3_ATTR_NORETURN_H                        /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_NORETURN_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_NORETURN.
- */
-#include "ruby/3/compiler_since.h"
-#include "ruby/3/has/attribute.h"
-#include "ruby/3/has/cpp_attribute.h"
-#include "ruby/3/has/declspec_attribute.h"
-
-/** Wraps (or simulates) `[[noreturn]]` */
-#if RUBY3_COMPILER_SINCE(SunPro, 5, 10, 0)
-# define RUBY3_ATTR_NORETURN() _Pragma("does_not_return")
-
-#elif RUBY3_HAS_DECLSPEC_ATTRIBUTE(noreturn)
-# define RUBY3_ATTR_NORETURN() __declspec(noreturn)
-
-#elif RUBY3_HAS_ATTRIBUTE(noreturn)
-# define RUBY3_ATTR_NORETURN() __attribute__((__noreturn__))
-
-#elif RUBY3_HAS_CPP_ATTRIBUTE(noreturn)
-# define RUBY3_ATTR_NORETURN() [[noreturn]]
-
-#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112)
-# define RUBY3_ATTR_NORETURN() _Noreturn
-
-#elif defined(_Noreturn)
-# /* glibc <sys/cdefs.h> has this macro. */
-# define RUBY3_ATTR_NORETURN() _Noreturn
-
-#else
-# define RUBY3_ATTR_NORETURN() /* void */
-#endif
-
-#endif /* RUBY3_ATTR_NORETURN_H */
diff --git a/include/ruby/3/attr/pure.h b/include/ruby/3/attr/pure.h
deleted file mode 100644
index b9ab3622ca..0000000000
--- a/include/ruby/3/attr/pure.h
+++ /dev/null
@@ -1,43 +0,0 @@
-#ifndef RUBY3_ATTR_PURE_H                            /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_PURE_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_PURE.
- */
-#include "ruby/3/compiler_since.h"
-#include "ruby/3/has/attribute.h"
-#include "ruby/assert.h"
-
-/** Wraps (or simulates) `__attribute__((pure))` */
-#if RUBY3_HAS_ATTRIBUTE(pure)
-# define RUBY3_ATTR_PURE() __attribute__((__pure__))
-#elif RUBY3_COMPILER_SINCE(SunPro, 5, 10, 0)
-# define RUBY3_ATTR_PURE() _Pragma("does_not_write_global_data")
-#else
-# define RUBY3_ATTR_PURE() /* void */
-#endif
-
-/** Enables #RUBY3_ATTR_PURE iff. #RUBY_NDEBUG. */
-#if RUBY_NDEBUG
-# define RUBY3_ATTR_PURE_ON_NDEBUG() RUBY3_ATTR_PURE()
-#else
-# define RUBY3_ATTR_PURE_ON_NDEBUG() /* void */
-#endif
-
-#endif /* RUBY3_ATTR_PURE_H */
diff --git a/include/ruby/3/attr/restrict.h b/include/ruby/3/attr/restrict.h
deleted file mode 100644
index 95c85f45ce..0000000000
--- a/include/ruby/3/attr/restrict.h
+++ /dev/null
@@ -1,45 +0,0 @@
-#ifndef RUBY3_ATTR_RESTRICT_H                        /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_RESTRICT_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_RESTRICT.
- */
-#include "ruby/3/compiler_since.h"
-#include "ruby/3/has/attribute.h"
-#include "ruby/3/token_paste.h"
-
-/* :FIXME:  config.h  includes conflicting  `#define  restrict`.   MSVC can  be
- * detected  using  `RUBY3_COMPILER_SINCE()`, but  Clang  &  family cannot  use
- * `__has_declspec_attribute()` which involves macro substitution. */
-
-/** Wraps (or simulates) `__declspec(restrict)` */
-#if RUBY3_COMPILER_SINCE(MSVC, 14, 0, 0)
-# define RUBY3_ATTR_RESTRICT() __declspec(RUBY3_TOKEN_PASTE(re, strict))
-
-#elif RUBY3_HAS_ATTRIBUTE(malloc)
-# define RUBY3_ATTR_RESTRICT() __attribute__((__malloc__))
-
-#elif RUBY3_COMPILER_SINCE(SunPro, 5, 10, 0)
-# define RUBY3_ATTR_RESTRICT() _Pragma("returns_new_memory")
-
-#else
-# define RUBY3_ATTR_RESTRICT() /* void */
-#endif
-
-#endif /* RUBY3_ATTR_RESTRICT_H */
diff --git a/include/ruby/3/attr/returns_nonnull.h b/include/ruby/3/attr/returns_nonnull.h
deleted file mode 100644
index 786e7e72ee..0000000000
--- a/include/ruby/3/attr/returns_nonnull.h
+++ /dev/null
@@ -1,37 +0,0 @@
-#ifndef RUBY3_ATTR_RETURNS_NONNULL_H                 /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_RETURNS_NONNULL_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_RETURNS_NONNULL.
- */
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((returns_nonnull))` */
-#if defined(_Ret_nonnull_)
-# /* Take SAL definition. */
-# define RUBY3_ATTR_RETURNS_NONNULL() _Ret_nonnull_
-
-#elif RUBY3_HAS_ATTRIBUTE(returns_nonnull)
-# define RUBY3_ATTR_RETURNS_NONNULL() __attribute__((__returns_nonnull__))
-
-#else
-# define RUBY3_ATTR_RETURNS_NONNULL() /* void */
-#endif
-
-#endif /* RUBY3_ATTR_RETURNS_NONNULL_H */
diff --git a/include/ruby/3/attr/warning.h b/include/ruby/3/attr/warning.h
deleted file mode 100644
index a83537e209..0000000000
--- a/include/ruby/3/attr/warning.h
+++ /dev/null
@@ -1,32 +0,0 @@
-#ifndef RUBY3_ATTR_WARNING_H                         /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_WARNING_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_WARNING.
- */
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((warning))` */
-#if RUBY3_HAS_ATTRIBUTE(warning)
-# define RUBY3_ATTR_WARNING(msg) __attribute__((__warning__ msg))
-#else
-# define RUBY3_ATTR_WARNING(msg) /* void */
-#endif
-
-#endif /* RUBY3_ATTR_WARNING_H */
diff --git a/include/ruby/3/attr/weakref.h b/include/ruby/3/attr/weakref.h
deleted file mode 100644
index e9c38f92e7..0000000000
--- a/include/ruby/3/attr/weakref.h
+++ /dev/null
@@ -1,32 +0,0 @@
-#ifndef RUBY3_ATTR_WEAKREF_H                         /*-*-C++-*-vi:se ft=cpp:*/
-#define RUBY3_ATTR_WEAKREF_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_WEAKREF.
- */
-#include "ruby/3/has/attribute.h"
-
-/** Wraps (or simulates) `__attribute__((weakref))` */
-#if RUBY3_HAS_ATTRIBUTE(weakref)
-# define RUBY3_ATTR_WEAKREF(sym) __attribute__((__weakref__(# sym)))
-#else
-# define RUBY3_ATTR_WEAKREF(sym) /* void */
-#endif
-
-#endif /* RUBY3_ATTR_WEAKREF_H */