From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp002.apm-internet.net (smtp002.apm-internet.net [85.119.248.221]) by sourceware.org (Postfix) with ESMTPS id B70573857351 for ; Thu, 29 Sep 2022 18:25:46 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org B70573857351 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=sandoe.co.uk Authentication-Results: sourceware.org; spf=none smtp.mailfrom=sandoe.co.uk Received: (qmail 47385 invoked from network); 29 Sep 2022 18:25:45 -0000 X-APM-Out-ID: 16644759454738 X-APM-Authkey: 257869/1(257869/1) 15 Received: from unknown (HELO ?192.168.1.95?) (81.138.1.83) by smtp002.apm-internet.net with SMTP; 29 Sep 2022 18:25:45 -0000 Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.120.23.2.7\)) Subject: Re: [PATCH] rs6000: Rework option -mpowerpc64 handling [PR106680] From: Iain Sandoe In-Reply-To: <20220929170437.GX25951@gate.crashing.org> Date: Thu, 29 Sep 2022 19:25:44 +0100 Cc: "Kewen.Lin" , GCC Patches Content-Transfer-Encoding: quoted-printable Message-Id: References: <9d9f1f43-b528-387d-45a7-1d89400de0fc@linux.ibm.com> <5B4DCBBB-3237-4A9F-ACCA-6669DE6905B8@sandoe.co.uk> <92415AC8-4A5A-4119-BFCC-D7C66472F961@sandoe.co.uk> <5e64fed0-7e79-3d60-da62-5c2bf3e2c707@linux.ibm.com> <75315B0E-9812-4726-A7FA-57762A2E47B7@sandoe.co.uk> <20220929170437.GX25951@gate.crashing.org> To: Segher Boessenkool X-Mailer: Apple Mail (2.3608.120.23.2.7) X-Spam-Status: No, score=-8.4 required=5.0 tests=BAYES_00,KAM_COUK,KAM_DMARC_STATUS,KAM_LAZY_DOMAIN_SECURITY,RCVD_IN_DNSWL_LOW,SPF_HELO_NONE,SPF_NONE,TXREP autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: Hi Segher > On 29 Sep 2022, at 18:04, Segher Boessenkool = wrote: > On Thu, Sep 29, 2022 at 09:16:33AM +0100, Iain Sandoe wrote: >> OK. So one small wrinkle,=20 >>=20 >> Darwin already has=20 >>=20 >> if (TARGET_64BIT && ! TARGET_POWERPC64) >> { >> rs6000_isa_flags |=3D OPTION_MASK_POWERPC64; >> warning (0, "%qs requires PowerPC64 architecture, enabling", = "-m64"); >> } >>=20 >> in darwin_rs6000_override_options() >=20 > This should be in generic code, there is nothing special about Darwin > for this. All 64-bit ABIs require 64-bit insns (stdu for example). Fine by me. >> Which means that we do not report an error, but a warning, and then = we force 64b on (taking >> the user=E2=80=99s intention to be specified by the explicit = =E2=80=98-m64=E2=80=99). >=20 > And that is wrong. Any silent overriding of what the user says is = bad. It is not silent - it warns and then carries on,=20 > Not overriding it (and then later ICEing) is bad as well, so it should > be an error here. And in generic code anyway. As noted, if that change is made we will see what the fallout is :) cheers Iain