From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 97136 invoked by alias); 14 Jul 2015 15:02:23 -0000 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org Received: (qmail 97088 invoked by uid 48); 14 Jul 2015 15:02:19 -0000 From: "ian at airs dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug go/66870] split stack issues on ppc64le and ppc64 Date: Tue, 14 Jul 2015 15:02:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: go X-Bugzilla-Version: 6.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: ian at airs dot com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: ian at airs dot com X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2015-07/txt/msg01139.txt.bz2 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66870 --- Comment #1 from Ian Lance Taylor --- The various issues in this bug are in different parts of the code base. The bug is assigned to me, but, to be clear, I have no plans to work on anything in the PPC-specific code. For x86, TARGET_CAN_SPLIT_STACK is defined in gcc/config/i386/gnu-user-common.h. The intent of the code in gospec.c is to pass -fsplit-stack and -Wl,-u,pthread_create when linking. When compiling, split stack is turned on by the code in go_langhook_init_options_struct in gcc/go/go-lang.c. When linking, we want to pass -fsplit-stack so that gcc/gcc.c uses STACK_SPLIT_SPEC. If the target defines TARGET_CAN_SPLIT_STACK for all cases where it might support it, I think the code will more or less work even for cases where split stack is not supported. If we don't pass those options, then the split-stack code will not work entirely correctly because new threads won't know their stack size.