From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 81896 invoked by alias); 5 Dec 2016 22:12:51 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 81877 invoked by uid 89); 5 Dec 2016 22:12:50 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.8 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=ham version=3.3.2 spammy=H*f:sk:bXMPXN9, H*MI:sk:8467344, H*MI:sk:bXMPXN9, H*MI:sk:1518726 X-HELO: smtp.eu.adacore.com Received: from mel.act-europe.fr (HELO smtp.eu.adacore.com) (194.98.77.210) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 05 Dec 2016 22:12:36 +0000 Received: from localhost (localhost [127.0.0.1]) by filtered-smtp.eu.adacore.com (Postfix) with ESMTP id EFF70812E2; Mon, 5 Dec 2016 23:12:33 +0100 (CET) Received: from smtp.eu.adacore.com ([127.0.0.1]) by localhost (smtp.eu.adacore.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9JNCvNxuBoaE; Mon, 5 Dec 2016 23:12:33 +0100 (CET) Received: from polaris.localnet (bon31-6-88-161-99-133.fbx.proxad.net [88.161.99.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.eu.adacore.com (Postfix) with ESMTPSA id B58F7812E4; Mon, 5 Dec 2016 23:12:33 +0100 (CET) From: Eric Botcazou To: Ian Lance Taylor Cc: gcc-patches@gcc.gnu.org, "Lynn A. Boger" Subject: Re: [patch v2] Get rid of stack trampolines for nested functions (1/4) Date: Mon, 05 Dec 2016 22:12:00 -0000 Message-ID: <3049494.GQlGFrCAi9@polaris> User-Agent: KMail/4.14.10 (Linux/3.16.7-48-desktop; KDE/4.14.9; x86_64; ; ) In-Reply-To: References: <1518726.5fkcUnkpqM@arcturus.home> <8467344.X3JSntxAug@arcturus.home> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-SW-Source: 2016-12/txt/msg00394.txt.bz2 > According to https://golang.org/cl/18200, this change broke Go on PPC64le. Any other platform where this also happened? > I haven't investigated myself and I don't know why. Go does not use > stack trampolines for function closures. It does use function > closures, but they are built on the heap. It also uses closures > mediated by libffi. The Go frontend does not enable custom function > descriptors. There are a couple of changes to the RTL expander for calls; they are supposed to be transparent but they might have tripped on a latent issue. > It should be possible to recreate the problem by configuring with > --enable-languages=go and running `make > RUNTESTFLAGS="go-test.exp=recover.go" check-gcc-go`. Thanks, I'll try to reproduce tomorrow. -- Eric Botcazou