From owner-svn-src-all@FreeBSD.ORG Thu Mar 26 16:00:36 2015 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 82DC8681; Thu, 26 Mar 2015 16:00:36 +0000 (UTC) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 56453EDA; Thu, 26 Mar 2015 16:00:36 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.9/8.14.9) with ESMTP id t2QG0aI5045102; Thu, 26 Mar 2015 16:00:36 GMT (envelope-from pfg@FreeBSD.org) Received: (from pfg@localhost) by svn.freebsd.org (8.14.9/8.14.9/Submit) id t2QG0as2045101; Thu, 26 Mar 2015 16:00:36 GMT (envelope-from pfg@FreeBSD.org) Message-Id: <201503261600.t2QG0as2045101@svn.freebsd.org> X-Authentication-Warning: svn.freebsd.org: pfg set sender to pfg@FreeBSD.org using -f From: "Pedro F. Giffuni" Date: Thu, 26 Mar 2015 16:00:36 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r280700 - head/sys/sys X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 26 Mar 2015 16:00:36 -0000 Author: pfg Date: Thu Mar 26 16:00:35 2015 New Revision: 280700 URL: https://svnweb.freebsd.org/changeset/base/280700 Log: Introduce some allocation function attributes. Bring support for two gcc function attributes that are likely to be used in our system headers: __alloc_size The alloc_size attribute is used to tell the compiler that the function return value points to memory, where the size is given by one or two of the functions parameters. __result_use_check Causes a warning to be emitted if a caller of the function with this attribute does not use its return value. This is known in gcc as "warn_unused_result" but we considered the original naming unsuitable for an attribute. The __alloc_size attribute required some workarounds for lint(1). Both attributes are supported by clang. Also see: D2107 MFC after: 3 days Modified: head/sys/sys/cdefs.h Modified: head/sys/sys/cdefs.h ============================================================================== --- head/sys/sys/cdefs.h Thu Mar 26 15:54:54 2015 (r280699) +++ head/sys/sys/cdefs.h Thu Mar 26 16:00:35 2015 (r280700) @@ -40,6 +40,9 @@ * Testing against Clang-specific extensions. */ +#ifndef __has_attribute +#define __has_attribute(x) 0 +#endif #ifndef __has_extension #define __has_extension __has_feature #endif @@ -209,6 +212,7 @@ #define __unused #define __packed #define __aligned(x) +#define __alloc_size(...) #define __section(x) #define __weak #else @@ -233,6 +237,11 @@ #define __aligned(x) __attribute__((__aligned__(x))) #define __section(x) __attribute__((__section__(x))) #endif +#if __has_attribute(alloc_size) || __GNUC_PREREQ__(4, 3) +#define __alloc_size(...) __attribute__((alloc_size(__VA_ARGS__))) +#else +#define __alloc_size(...) +#endif #if defined(__INTEL_COMPILER) #define __dead2 __attribute__((__noreturn__)) #define __pure2 __attribute__((__const__)) @@ -242,7 +251,7 @@ #define __aligned(x) __attribute__((__aligned__(x))) #define __section(x) __attribute__((__section__(x))) #endif -#endif +#endif /* lint */ #if !__GNUC_PREREQ__(2, 95) #define __alignof(x) __offsetof(struct { char __a; x __b; }, __b) @@ -363,8 +372,10 @@ #if __GNUC_PREREQ__(3, 4) #define __fastcall __attribute__((__fastcall__)) +#define __result_use_check __attribute__((__warn_unused_result__)) #else #define __fastcall +#define __result_use_check #endif #if __GNUC_PREREQ__(4, 1)