From 4ff3f205408ff8bb413d69151105d301858136ba Mon Sep 17 00:00:00 2001 From: 卜部昌平 Date: Fri, 10 Apr 2020 14:11:40 +0900 Subject: 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 --- internal.h | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) (limited to 'internal.h') diff --git a/internal.h b/internal.h index 3c65164f3d..c39fa18174 100644 --- a/internal.h +++ b/internal.h @@ -1,17 +1,15 @@ -/********************************************************************** - - internal.h - - - $Author$ - created at: Tue May 17 11:42:20 JST 2011 - - Copyright (C) 2011 Yukihiro Matsumoto - -**********************************************************************/ - -#ifndef RUBY_INTERNAL_H +#ifndef RUBY_INTERNAL_H /*-*-C-*-vi:se ft=c:*/ #define RUBY_INTERNAL_H 1 - +/** + * @file + * @author $Author$ + * @date Tue May 17 11:42:20 JST 2011 + * @copyright Copyright (C) 2011 Yukihiro Matsumoto + * @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. + */ #include "ruby/3/config.h" #ifdef __cplusplus -- cgit v1.2.3