From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_EF,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id E109B1F4B5 for ; Thu, 21 Nov 2019 13:23:25 +0000 (UTC) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; q=dns; s= default; b=PLjkXUPcy0C8PNw6XCv/7MxF3PLiOa8bhhNS6NBntBUnHgD3bK5Ww B+FJjUZLIC5QxGsVVa+cfFY7eFKu6fyeX/iI6lxcBb9hv47wtRePEhwOP5vXoVqU t4qiPFdpczeqsQ9HdchFWL2OVPKI8mm9l7dHvdlWUHcLvOmFCD8ZSI= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; s=default; bh=VeUR+k2zLbx0UclYOIAgLomS7IE=; b=si3pTSmNHmf819U/V5ARVTPb31/N yI81eM2pKHkIuOH478UZ/fYIWc/9VRJ1xrTse1g0omVSXinna8cRBXbPPpVhYPm5 CbFSmNEnGK2qhKz+VzQWjlLOcrUx9xgAMwO58WbFwydxQqQfWr3tfymAUdM7J7pQ ekkWZgkNV/R+zHI= Received: (qmail 1264 invoked by alias); 21 Nov 2019 13:23:23 -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 Received: (qmail 1256 invoked by uid 89); 21 Nov 2019 13:23:23 -0000 Authentication-Results: sourceware.org; auth=none X-HELO: emiliocobos.net From: =?UTF-8?q?Emilio=20Cobos=20=C3=81lvarez?= Authentication-Results: mail.emiliocobos.net; dmarc=none (p=none dis=none) header.from=crisal.io To: Florian Weimer , libc-alpha@sourceware.org Cc: =?UTF-8?q?Emilio=20Cobos=20=C3=81lvarez?= Subject: [PATCH v2] libc: Don't use a custom wrapper macro around __has_include. Date: Thu, 21 Nov 2019 14:21:01 +0100 Message-Id: <20191121132101.84999-1-emilio@crisal.io> In-Reply-To: <875zjdo045.fsf@oldenburg2.str.redhat.com> References: <875zjdo045.fsf@oldenburg2.str.redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This causes issues when using clang with -frewrite-includes to e.g., submit the translation unit to a distributed compiler. In my case, I was building Firefox using sccache. See [1] for a reduced test-case since I initially thought this was a clang bug, and [2] for more context. Apparently doing this is invalid C++ per [cpp.cond], which mentions [3]: > The #ifdef and #ifndef directives, and the defined conditional inclusion > operator, shall treat __has_include and __has_cpp_attribute as if they > were the names of defined macros. The identifiers __has_include and > __has_cpp_attribute shall not appear in any context not mentioned in this > subclause. [1]: https://bugs.llvm.org/show_bug.cgi?id=43982 [2]: https://bugs.llvm.org/show_bug.cgi?id=37990 [3]: http://eel.is/c++draft/cpp.cond#7.sentence-2 --- misc/sys/cdefs.h | 8 -------- sysdeps/unix/sysv/linux/bits/statx.h | 12 +++++++----- 2 files changed, 7 insertions(+), 13 deletions(-) diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h index abcb0d5e3c..467dbd9547 100644 --- a/misc/sys/cdefs.h +++ b/misc/sys/cdefs.h @@ -412,14 +412,6 @@ # define __glibc_has_attribute(attr) 0 #endif -#ifdef __has_include -/* Do not use a function-like macro, so that __has_include can inhibit - macro expansion. */ -# define __glibc_has_include __has_include -#else -# define __glibc_has_include(header) 0 -#endif - #if (!defined _Noreturn \ && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \ && !__GNUC_PREREQ (4,7)) diff --git a/sysdeps/unix/sysv/linux/bits/statx.h b/sysdeps/unix/sysv/linux/bits/statx.h index ff3f2e8973..2015c8262e 100644 --- a/sysdeps/unix/sysv/linux/bits/statx.h +++ b/sysdeps/unix/sysv/linux/bits/statx.h @@ -26,11 +26,13 @@ /* Use "" to work around incorrect macro expansion of the __has_include argument (GCC PR 80005). */ -#if __glibc_has_include ("linux/stat.h") -# include "linux/stat.h" -# ifdef STATX_TYPE -# define __statx_timestamp_defined 1 -# define __statx_defined 1 +#ifdef __has_include +# if __has_include ("linux/stat.h") +# include "linux/stat.h" +# ifdef STATX_TYPE +# define __statx_timestamp_defined 1 +# define __statx_defined 1 +# endif # endif #endif -- 2.24.0