From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D0D7DCA0EFF for ; Sat, 30 Aug 2025 22:57:49 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1usUVI-0001sI-Ew; Sat, 30 Aug 2025 18:57:00 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1usUVG-0001rO-Im; Sat, 30 Aug 2025 18:56:58 -0400 Received: from mx.treblig.org ([2a00:1098:5b::1]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1usUVE-0004Nq-EU; Sat, 30 Aug 2025 18:56:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=treblig.org ; s=bytemarkmx; h=Content-Type:MIME-Version:Message-ID:Subject:From:Date:From :Subject; bh=NUh6bO8L0LYDQR9o9qVeYCHHW269TxHhGS6wdWMt4Ow=; b=gorBBJXyVvHbXmmZ 1RIZef+3yJ1CkSGY/CiigIWhnNZpyRczBvjyR/m44BCsJa+4XhnfddGUsVkowvLWbrkgKz1XdP+ao JgZnz2G67XCevmT8+OzkF5QHu3mhgTqz7WhiP3cfyiDHTEYH+vJZOdI9rbVqU8IaNFycBgISR6Fnc z3T0G4ItH+lqxs6UPYnrBYcWLcBzR0J/EhB4uL2AeZISVMZJZ1TGkdUelxjow15vpkf5RCr55UCj8 fE0gwlTczdOi2bVDLuU4sJT+cfTwJtALaESrdHTtSY+hG8z/3M1or5NFlvf6mw/zm1GTVHMcWqV1f Za31i/CbRAGdk/S40g==; Received: from dg by mx.treblig.org with local (Exim 4.96) (envelope-from ) id 1usUV8-007aU9-2r; Sat, 30 Aug 2025 22:56:50 +0000 Date: Sat, 30 Aug 2025 22:56:50 +0000 From: "Dr. David Alan Gilbert" To: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= Cc: qemu-devel@nongnu.org, Stefan Weil , qemu-block@nongnu.org, Manos Pitsidianakis , Kevin Wolf , Hanna Reitz , Gerd Hoffmann , Christian Schoenebeck , Markus Armbruster , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau , Paolo Bonzini , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= Subject: Re: [PATCH v2 01/14] include: define constant for early constructor priority Message-ID: References: <20250829180354.2922145-1-berrange@redhat.com> <20250829180354.2922145-2-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20250829180354.2922145-2-berrange@redhat.com> X-Chocolate: 70 percent or better cocoa solids preferably X-Operating-System: Linux/6.1.0-34-amd64 (x86_64) X-Uptime: 22:56:44 up 125 days, 7:10, 1 user, load average: 0.00, 0.00, 0.00 User-Agent: Mutt/2.2.12 (2023-09-09) Received-SPF: pass client-ip=2a00:1098:5b::1; envelope-from=dg@treblig.org; helo=mx.treblig.org X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org * Daniel P. Berrangé (berrange@redhat.com) wrote: > Functions marked with __attribute__((__constructor__)) will be > invoked in linker order. In theory this is well defined, but > in practice, it is hard to determine what this order will be > with the layers of indirection through meson, ninja and the > static libraries QEMU builds. > > Notably, the order currently appears different between Linux > and Windows (as tested with Wine on Linux). This can cause > problems when certain QEMU constructors have a dependancy on > other QEMU constructors. > > To address this define a QEMU_CONSTRUCTOR_EARLY constant which > provides a priority value that will run before other default > constructors. This is to be used for QEMU constructors that > are themselves self-contained, but may be relied upon by other > constructors. > > Signed-off-by: Daniel P. Berrangé Reviewed-by: Dr. David Alan Gilbert > --- > include/qemu/compiler.h | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/include/qemu/compiler.h b/include/qemu/compiler.h > index 1c2b673c05..4c49f52eb0 100644 > --- a/include/qemu/compiler.h > +++ b/include/qemu/compiler.h > @@ -194,6 +194,14 @@ > # define QEMU_USED > #endif > > +/* > + * A priority for __attribute__((constructor(...))) that > + * will run earlier than the default constructors. Must > + * only be used for functions that have no dependency > + * on global initialization of other QEMU subsystems. > + */ > +#define QEMU_CONSTRUCTOR_EARLY 101 > + > /* > * Disable -ftrivial-auto-var-init on a local variable. > * > -- > 2.50.1 > -- -----Open up your eyes, open up your mind, open up your code ------- / Dr. David Alan Gilbert | Running GNU/Linux | Happy \ \ dave @ treblig.org | | In Hex / \ _________________________|_____ http://www.treblig.org |_______/