From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 6C63646AE2; Thu, 3 Jul 2025 10:12:29 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id ECE0240287; Thu, 3 Jul 2025 10:12:28 +0200 (CEST) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by mails.dpdk.org (Postfix) with ESMTP id 218E640285 for ; Thu, 3 Jul 2025 10:12:27 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1751530346; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lGhuhlbEdRYjPaF69scpLgSkjCduppQ6KuKU/B2UJKM=; b=IgX0Tx7QC9qArap3l1adX5Bq+HDdBGU0Q73tM5xXBLGpHGenPeiKDqJrhJxl+o1zwa6D/K AXZmFFFUoqTEkOqBYc26m41C7a+RzTgPc6SyXnFv14bdSoEn3PiGMtBs2Zm5PD+2wM7gUB mXVukAAG7Mgpiqhkmis/legRgo6r6ZQ= Received: from mail-lj1-f198.google.com (mail-lj1-f198.google.com [209.85.208.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-357-lv5a6z82N7aCEzg4gS5ogQ-1; Thu, 03 Jul 2025 04:12:25 -0400 X-MC-Unique: lv5a6z82N7aCEzg4gS5ogQ-1 X-Mimecast-MFC-AGG-ID: lv5a6z82N7aCEzg4gS5ogQ_1751530343 Received: by mail-lj1-f198.google.com with SMTP id 38308e7fff4ca-32b4a06b780so33093991fa.0 for ; Thu, 03 Jul 2025 01:12:24 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751530343; x=1752135143; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=lGhuhlbEdRYjPaF69scpLgSkjCduppQ6KuKU/B2UJKM=; b=XFeciFeAjy8+eg6MyuGns3E+vG4nkVpGoZ17qEydBNO8DpuPaaH3QSccWBQeHvUgN3 YzJIW4sz64mXQO7RYGl+of6l4bPhG5btkv8z3+OUC4pBgBhNidTfntLDDe6A8g9Ekx9v XVL8hexhWBQvC9CEUQB4kjUHxwJgybFmFEG2rV1iWfWzUC241O+oaFQ4ESrDjWqVwywL +BmFgpPo05J96Otstm/VEG4jEo3acy2lfmSoIW4IC2wzbYcpKPGhN7CWPfFiYQOS4sDZ dquxp1VJCQ4bHeCAzsXLLM3hikRaIO0bccZNdVSc1pukhrWNVS7q5vCjwDjlZs7b6N7i N+ng== X-Forwarded-Encrypted: i=1; AJvYcCVU7eqIf/wy5alapUPmpBll9oYVDz87MWHMDNjnEDAkc0C9tTGVHuqgMwWLetSZkg7OWi4=@dpdk.org X-Gm-Message-State: AOJu0YwQtFBVyg4rFFQArC0//wiGOpBl9y46hPVNGDbb9k8X3wgXCAYa KKf7Y9Vy90MjZDfaxc0ibmZ1BMMXqYf5MgkHwC6hCyAzAD7+aUvw110zEY7ckfEpldnTAvQXt3D u7Z9ey7tJr8/Hi5RpHreWlkWDL0eJwLqvfeixy8NXesmjAYlc2ToYJTnNh1cKjNCwz3X3lsNADI /yY4WsPbpx8lyvT29d/Tw= X-Gm-Gg: ASbGncuoVUp8s+rSgtNe6GfPxPjfvEObzvjJfC0ImoA3FvFfvgnrajRRQpxwNi4/svp boJ8eu1o2BGl0mJgMo5jE2kK+PhWqeohF0qlDND3lHtTgdV5q+E+5YxjTb+9CZSwyXjJbwCbgws Vcwjg18g== X-Received: by 2002:a2e:aa8c:0:b0:32b:4f0c:d259 with SMTP id 38308e7fff4ca-32dfff9aabemr18985911fa.16.1751530343223; Thu, 03 Jul 2025 01:12:23 -0700 (PDT) X-Google-Smtp-Source: AGHT+IFzXbpluqi6e2a103lgafEOwwB6GYLXEHVyMY4gIb1L4L4HXAcESUuBrWKZz5KdLb2gmQVX81EGBG84ujN9sfU= X-Received: by 2002:a2e:aa8c:0:b0:32b:4f0c:d259 with SMTP id 38308e7fff4ca-32dfff9aabemr18985801fa.16.1751530342729; Thu, 03 Jul 2025 01:12:22 -0700 (PDT) MIME-Version: 1.0 References: <20250702155129.3440210-1-bruce.richardson@intel.com> <20250702160138.3441279-1-bruce.richardson@intel.com> <20250702112242.7b93d978@hermes.local> In-Reply-To: From: David Marchand Date: Thu, 3 Jul 2025 10:12:10 +0200 X-Gm-Features: Ac12FXyDUJvaJMpO7tT-UNWfrl_kgY2Y4ZmFPJmW0vbJuB9Aq0F3HipAXaK5vSM Message-ID: Subject: Re: [PATCH v2] build/x86: fix support for older compilers To: Bruce Richardson Cc: Stephen Hemminger , dev@dpdk.org, Konstantin Ananyev , Vipin Varghese X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: aZUTGQlK4uxLEqyk911P9oDtb4xV3uVrgsfkXi0VjqI_1751530343 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org On Thu, Jul 3, 2025 at 10:01=E2=80=AFAM Bruce Richardson wrote: > > On Wed, Jul 02, 2025 at 11:22:42AM -0700, Stephen Hemminger wrote: > > On Wed, 2 Jul 2025 17:00:45 +0100 > > Bruce Richardson wrote: > > > > > Some older compilers e.g. gcc 8.5, do not support overriding > > > -march=3Dnative with another architecture, leading to build warnings = such > > > as reported in Bugzilla (link below). Add a check for that case, and > > > explicitly add the avx512 flags if necessary. > > > > > > Note: it appears that it is only the "native" flag that isn't > > > overridden, which makes the issue hard to reproduce e.g. using > > > godbolt.org, or on a modern machine. For example, testing with gcc 8.= 5 > > > on a haswell machine, using 'native' vs explicit 'haswell': > > > > > > gcc -march=3Dnative -march=3Dskylake-avx512 -dM -E - < /dev/null | gr= ep AVX512 | wc -l > > > 0 > > > > > > gcc -march=3Dhaswell -march=3Dskylake-avx512 -dM -E - < /dev/null | g= rep AVX512 | wc -l > > > 5 > > > > > > Bugzilla ID: 1736 > > > Fixes: e361ae3f59d3 ("build: reduce use of AVX compiler flags") > > > > > > Signed-off-by: Bruce Richardson > > > --- > > > config/x86/meson.build | 7 ++++++- > > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > > > diff --git a/config/x86/meson.build b/config/x86/meson.build > > > index e2ccfb6d12..0dcc5ddee4 100644 > > > --- a/config/x86/meson.build > > > +++ b/config/x86/meson.build > > > @@ -71,8 +71,13 @@ avx512_march_flag =3D '-march=3Dx86-64-v4' > > > if not cc.has_argument(avx512_march_flag) > > > avx512_march_flag =3D '-march=3Dskylake-avx512' > > > endif > > > +# workaround for older compilers, e.g. gcc 8.5 on RHEL 8. > > > +# if march flag overriding doesn't work, explicitly add flags for AV= X512. > > > +if cc.get_define('__AVX512F__', args: [machine_args, avx512_march_fl= ag]) =3D=3D '' > > > + avx512_march_flag =3D ['-mavx512f', '-mavx512bw', '-mavx512cd', = '-mavx512dq', '-mavx512vl'] > > > +endif > > > > RHEL 8.5 reached end of extended support cycle (EOL). > > Why are we still supporting it? > > Folks working for Redhat can answer better than me, but according to [1] > it's not EOL yet. Also, we support it in DPDK because users are still usi= ng RHEL 8 is not EOL. --=20 David Marchand