From patchwork Sun Jul 31 20:09:24 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Zack Weinberg X-Patchwork-Id: 14175 Received: (qmail 9214 invoked by alias); 31 Jul 2016 20:09:38 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 9114 invoked by uid 89); 31 Jul 2016 20:09:37 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.9 required=5.0 tests=AWL, BAYES_00, RP_MATCHES_RCVD, SPF_PASS autolearn=ham version=3.3.2 spammy=1623, maj, H*r:166.84.1, H*r:sk:mailbac X-HELO: mailbackend.panix.com From: Zack Weinberg To: libc-alpha@sourceware.org Cc: adhemerval.zanella@linaro.org, vapier@gentoo.org, carlos@redhat.com Subject: [2.24 PATCH 3/3] Deprecate inclusion of by Date: Sun, 31 Jul 2016 16:09:24 -0400 Message-Id: MIME-Version: 1.0 In-Reply-To: References: The macros defined by are not part of POSIX nor XSI, and their names frequently collide with user code; see for instance glibc bug 19239 and Red Hat bug 130601. includes under _GNU_SOURCE, and C++ code presently cannot avoid being compiled under _GNU_SOURCE, exacerbating the problem. ChangeLog: * NEWS: Inclusion of by is deprecated. * misc/sys/sysmacros.h: If __SYSMACROS_DEPRECATED_INCLUSION is defined, define major, minor, and makedev to issue deprecation warnings on use. If __SYSMACROS_DEPRECATED_INCLUSION is *not* defined, suppress previously-activated deprecation warnings for these macros and prevent subsequent inclusions of this header from having any effect. * posix/sys/types.h: Define __SYSMACROS_DEPRECATED_INCLUSION before including , and undefine it again afterward. --- NEWS | 16 ++++++++++++++ misc/sys/sysmacros.h | 62 +++++++++++++++++++++++++++++++++++++++++++++++++--- posix/sys/types.h | 8 ++++++- 3 files changed, 82 insertions(+), 4 deletions(-) diff --git a/NEWS b/NEWS index e2737d5..f57cc99 100644 --- a/NEWS +++ b/NEWS @@ -47,6 +47,22 @@ Version 2.24 direction of negative infinity. These are currently enabled as GNU extensions. +* The inclusion of by is deprecated. This + means that in a future release, the macros “major”, “minor”, and “makedev” + will only be available from . + + These macros are not part of POSIX nor XSI, and their names frequently + collide with user code; see for instance glibc bug 19239 and Red Hat bug + 130601. includes under _GNU_SOURCE, and C++ code + presently cannot avoid being compiled under _GNU_SOURCE, exacerbating the + problem. + + Code that does not need these macros should #undef them after including + ; this will also improve portability to BSD-derived systems, + where these macros are unconditionally defined by . Code + that *does* need these macros should include , and then + include if __GLIBC__ is defined. + Security related changes: * An unnecessary stack copy in _nss_dns_getnetbyname_r was removed. It diff --git a/misc/sys/sysmacros.h b/misc/sys/sysmacros.h index dc2eb83..086e9af 100644 --- a/misc/sys/sysmacros.h +++ b/misc/sys/sysmacros.h @@ -16,6 +16,23 @@ License along with the GNU C Library; if not, see . */ +#ifndef _SYS_SYSMACROS_H_OUTER + +#ifndef __SYSMACROS_DEPRECATED_INCLUSION +# define _SYS_SYSMACROS_H_OUTER 1 +#endif + +/* If is included after , these macros + will already be defined, and we need to redefine them without the + deprecation warnings. (If they are included in the opposite order, + the outer #ifndef will suppress this entire file and the macros + will be usable without warnings.) */ +#undef major +#undef minor +#undef makedev + +/* This is the macro that must be defined to satisfy the misuse check + in bits/sysmacros.h. */ #ifndef _SYS_SYSMACROS_H #define _SYS_SYSMACROS_H 1 @@ -23,32 +40,65 @@ #include #include +/* The extra "\n " moves gcc's [-Wdeprecated-declarations] annotation + onto the next line. */ +#define __SYSMACROS_DEPRECATION_MSG(symbol) \ + "\n In the GNU C Library, `" #symbol "' is defined by ." \ + "\n For historical compatibility, it is currently defined by" \ + "\n as well, but we plan to remove this soon." \ + "\n To use `" #symbol "', include directly." \ + "\n If you did not intend to use a system-defined macro `" #symbol "'," \ + "\n you should #undef it after including ." \ + "\n " + #define __SYSMACROS_DECL_TEMPL(rtype, name, proto) \ extern rtype gnu_dev_##name proto __THROW __attribute_const__; +#define __SYSMACROS_FST_DECL_TEMPL(rtype, name, proto) \ + extern rtype __REDIRECT_NTH (__##name##_from_sys_types, proto, \ + gnu_dev_##name) \ + __attribute_const__ \ + __attribute_deprecated_msg__ (__SYSMACROS_DEPRECATION_MSG (name)); + #define __SYSMACROS_IMPL_TEMPL(rtype, name, proto) \ __extension__ __extern_inline __attribute_const__ rtype \ __NTH (gnu_dev_##name proto) +#define __SYSMACROS_FST_IMPL_TEMPL(rtype, name, proto) \ + __extension__ __extern_inline __attribute_const__ rtype \ + __NTH (__##name##_from_sys_types proto) + __BEGIN_DECLS __SYSMACROS_DECLARE_MAJOR (__SYSMACROS_DECL_TEMPL) __SYSMACROS_DECLARE_MINOR (__SYSMACROS_DECL_TEMPL) __SYSMACROS_DECLARE_MAKEDEV (__SYSMACROS_DECL_TEMPL) +__SYSMACROS_DECLARE_MAJOR (__SYSMACROS_FST_DECL_TEMPL) +__SYSMACROS_DECLARE_MINOR (__SYSMACROS_FST_DECL_TEMPL) +__SYSMACROS_DECLARE_MAKEDEV (__SYSMACROS_FST_DECL_TEMPL) + #ifdef __USE_EXTERN_INLINES __SYSMACROS_DEFINE_MAJOR (__SYSMACROS_IMPL_TEMPL) __SYSMACROS_DEFINE_MINOR (__SYSMACROS_IMPL_TEMPL) __SYSMACROS_DEFINE_MAKEDEV (__SYSMACROS_IMPL_TEMPL) +__SYSMACROS_DEFINE_MAJOR (__SYSMACROS_FST_IMPL_TEMPL) +__SYSMACROS_DEFINE_MINOR (__SYSMACROS_FST_IMPL_TEMPL) +__SYSMACROS_DEFINE_MAKEDEV (__SYSMACROS_FST_IMPL_TEMPL) + #endif __END_DECLS +#endif /* _SYS_SYSMACROS_H */ + #ifndef __SYSMACROS_NEED_IMPLEMENTATION # undef __SYSMACROS_DECL_TEMPL +# undef __SYSMACROS_FST_DECL_TEMPL # undef __SYSMACROS_IMPL_TEMPL +# undef __SYSMACROS_FST_IMPL_TEMPL # undef __SYSMACROS_DECLARE_MAJOR # undef __SYSMACROS_DECLARE_MINOR # undef __SYSMACROS_DECLARE_MAKEDEV @@ -57,8 +107,14 @@ __END_DECLS # undef __SYSMACROS_DEFINE_MAKEDEV #endif -#define major(dev) gnu_dev_major (dev) -#define minor(dev) gnu_dev_minor (dev) -#define makedev(maj, min) gnu_dev_makedev (maj, min) +#ifdef __SYSMACROS_DEPRECATED_INCLUSION +# define major(dev) __major_from_sys_types (dev) +# define minor(dev) __minor_from_sys_types (dev) +# define makedev(maj, min) __makedev_from_sys_types (maj, min) +#else +# define major(dev) gnu_dev_major (dev) +# define minor(dev) gnu_dev_minor (dev) +# define makedev(maj, min) gnu_dev_makedev (maj, min) +#endif #endif /* sys/sysmacros.h */ diff --git a/posix/sys/types.h b/posix/sys/types.h index a728567..83dadcd 100644 --- a/posix/sys/types.h +++ b/posix/sys/types.h @@ -218,8 +218,14 @@ typedef int register_t __attribute__ ((__mode__ (__word__))); /* It also defines `fd_set' and the FD_* macros for `select'. */ # include -/* BSD defines these symbols, so we follow. */ +/* BSD defines `major', `minor', and `makedev' in this header. + However, these symbols are likely to collide with user code, so we are + going to stop defining them here in an upcoming release. Code that needs + these macros should include directly. Code that does + not need these macros should #undef them after including this header. */ +# define __SYSMACROS_DEPRECATED_INCLUSION # include +# undef __SYSMACROS_DEPRECATED_INCLUSION #endif /* Use misc. */