Date: Sat, 20 Jul 2024 15:50:58 GMT From: Warner Losh <imp@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: eaa3d34b6220 - main - cdefs.9: Update for C++ environments Message-ID: <202407201550.46KFows8038621@gitrepo.freebsd.org>
next in thread | raw e-mail | index | archive | help
The branch main has been updated by imp: URL: https://cgit.FreeBSD.org/src/commit/?id=eaa3d34b6220d8858eabc622165ec4db2cc75e96 commit eaa3d34b6220d8858eabc622165ec4db2cc75e96 Author: Warner Losh <imp@FreeBSD.org> AuthorDate: 2024-07-20 14:38:52 +0000 Commit: Warner Losh <imp@FreeBSD.org> CommitDate: 2024-07-20 15:50:38 +0000 cdefs.9: Update for C++ environments We support all the C++ standards to some degree. However, pre C++11 standard support has been disappearing upstream, so also add a note about -pedantic-errors might not work for earlier standards. Add note about __cplusplus values. Sponsored by: Netflix --- share/man/man9/cdefs.9 | 43 +++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 41 insertions(+), 2 deletions(-) diff --git a/share/man/man9/cdefs.9 b/share/man/man9/cdefs.9 index 71b3e7fd4f81..dd45e3f61a9f 100644 --- a/share/man/man9/cdefs.9 +++ b/share/man/man9/cdefs.9 @@ -3,7 +3,7 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" -.Dd July 18, 2024 +.Dd July 20, 2024 .Dt CDEFS 9 .Os .Sh NAME @@ -281,7 +281,7 @@ still uses these. supports a number C standard environments. Selection of the language dialect is a compiler-dependent command line option, though it is usually -.Fl cstd=XX +.Fl std=XX where XX is the standard to set for compiling, such as c89 or c23. .Fx provides a number of selection macros to control visibility of symbols. @@ -402,6 +402,45 @@ extensions are visible, 0 otherwise. .St -isoC-2011 Appendix K 3.7.4.1 extensions are visible, 0 otherwise. +.Sh Supported C++ Environments +.Fx +supports C++11 and newer standards fully. +.Bl -tag +.It ISO/IEC 14882:1998 ("C++98") +.Dv __cplusplus = 199711 +.Pp +The first standardized version of C++. +Unlike K \*(Am R support in C, compilers dropped support for versions of +the language prior to C++98. +.It ISO/IEC 14882:2003 ("C++03") +.Dv __cplusplus = 199711 +.Pp +Note, this is the same value as C++98. +C++03 did not define a new value for +.Dv __cplusplus . +There is no way, at compile time, to detect the difference. +The standard resolved a number of defect reports and slightly +expanded value initialization. +Most compilers support it the same as C++98. +.It ISO/IEC 14882:2011 ("C++11") +.Dv __cplusplus = 201103 +.It ISO/IEC 14882:2014 ("C++14") +.Dv __cplusplus = 201402 +.It ISO/IEC 14882:2017 ("C++17") +.Dv __cplusplus = 201703 +.It ISO/IEC 14882:2020 ("C++20") +.Dv __cplusplus = 202002 +.It ISO/IEC 14882:2023 ("C++23") +.Dv __cplusplus = 202302 +.El +.Pp +.Fx +uses llvm project's libc++. +However, they are removing support for C++ prior to C++11. +While programs can still build with earlier environments for now, these changes +mean that +.Fl pedantic-errors +cannot be reliably enabled for standards older than C++11. .Sh HISTORY .In sys/cdefs.h first appeared in
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?202407201550.46KFows8038621>