kotovalexarian-likes-github/ruby--ruby
1
0
Fork 0
mirror of https://github.com/ruby/ruby.git synced 2022-11-09 12:17:21 -05:00
Code Releases Activity
ruby--ruby/include/ruby/impl/attr/artificial.h

47 lines
2.4 KiB
C
Raw Normal View History

add #include guard hack According to MSVC manual (*1), cl.exe can skip including a header file when that: - contains #pragma once, or - starts with #ifndef, or - starts with #if ! defined. GCC has a similar trick (*2), but it acts more stricter (e. g. there must be _no tokens_ outside of #ifndef...#endif). Sun C lacked #pragma once for a looong time. Oracle Developer Studio 12.5 finally implemented it, but we cannot assume such recent version. This changeset modifies header files so that each of them include strictly one #ifndef...#endif. I believe this is the most portable way to trigger compiler optimizations. [Bug #16770] *1: https://docs.microsoft.com/en-us/cpp/preprocessor/once *2: https://gcc.gnu.org/onlinedocs/cppinternals/Guard-Macros.html
2020-04-10 01:11:40 -04:00
#ifndef RUBY3_ATTR_ARTIFICIAL_H /*-*-C++-*-vi:se ft=cpp:*/
#define RUBY3_ATTR_ARTIFICIAL_H
/**
Merge pull request #2991 from shyouhei/ruby.h Split ruby.h
2020-04-08 00:28:13 -04:00
* @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 what you use. This reverts commit 443389effc37308ce1a3c3a840082a344fc6af56. This reverts commit d94960f22ec2de3a3855305cb51343806d2b46c7. Inclusion of header files must be explicit. Every file shall directly include what is necessary. https://github.com/include-what-you-use/include-what-you-use says: > When every file includes what it uses, then it is possible to edit any > file and remove unused headers, without fear of accidentally breaking > the upwards dependencies of that file. It also becomes easy to > automatically track and update dependencies in the source code. Though we don't use iwyu itself, the principle quoted above is a good thing that we can agree. Now that include guards were added to every and all of the headers inside of our project this changeset does not increase compile time, at least on my machine.
2020-04-12 02:42:45 -04:00
#include "ruby/3/has/attribute.h"
Merge pull request #2991 from shyouhei/ruby.h Split ruby.h
2020-04-08 00:28:13 -04:00
/** Wraps (or simulates) `__attribute__((artificial))` */
add #include guard hack According to MSVC manual (*1), cl.exe can skip including a header file when that: - contains #pragma once, or - starts with #ifndef, or - starts with #if ! defined. GCC has a similar trick (*2), but it acts more stricter (e. g. there must be _no tokens_ outside of #ifndef...#endif). Sun C lacked #pragma once for a looong time. Oracle Developer Studio 12.5 finally implemented it, but we cannot assume such recent version. This changeset modifies header files so that each of them include strictly one #ifndef...#endif. I believe this is the most portable way to trigger compiler optimizations. [Bug #16770] *1: https://docs.microsoft.com/en-us/cpp/preprocessor/once *2: https://gcc.gnu.org/onlinedocs/cppinternals/Guard-Macros.html
2020-04-10 01:11:40 -04:00
#if RUBY3_HAS_ATTRIBUTE(artificial)
Merge pull request #2991 from shyouhei/ruby.h Split ruby.h
2020-04-08 00:28:13 -04:00
# define RUBY3_ATTR_ARTIFICIAL() __attribute__((__artificial__))
#else
# define RUBY3_ATTR_ARTIFICIAL() /* void */
#endif
add #include guard hack According to MSVC manual (*1), cl.exe can skip including a header file when that: - contains #pragma once, or - starts with #ifndef, or - starts with #if ! defined. GCC has a similar trick (*2), but it acts more stricter (e. g. there must be _no tokens_ outside of #ifndef...#endif). Sun C lacked #pragma once for a looong time. Oracle Developer Studio 12.5 finally implemented it, but we cannot assume such recent version. This changeset modifies header files so that each of them include strictly one #ifndef...#endif. I believe this is the most portable way to trigger compiler optimizations. [Bug #16770] *1: https://docs.microsoft.com/en-us/cpp/preprocessor/once *2: https://gcc.gnu.org/onlinedocs/cppinternals/Guard-Macros.html
2020-04-10 01:11:40 -04:00
#endif /* RUBY3_ATTR_ARTIFICIAL_H */
Copy permalink