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 B951CC636D7 for ; Tue, 21 Feb 2023 17:56:09 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pUWr7-0006if-DU; Tue, 21 Feb 2023 12:55:09 -0500 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 1pUWr5-0006i9-QB for qemu-devel@nongnu.org; Tue, 21 Feb 2023 12:55:07 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pUWr3-00066V-Lz for qemu-devel@nongnu.org; Tue, 21 Feb 2023 12:55:07 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1677002104; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=M6mFH2T2aQukEyErH6/agdfLPi9EAXxS3KlHceNJlYk=; b=IkavnJ3MFB32GbvLVF4Iw3N2A3zz7mA9r/2/3oQHRNZHGNguFTT7ud5kSB8dchBb7IgGwX O3EmxpCXdGP0B2rsi92Ub1fA5CMzggxfx57rmH6IEzSdvBzcXf0wYg8QHLOf0Ny5iiOcnh kVM+0Cq3JQoOdWQ2Hx/M+FSVbCtD4ac= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-450-XhLrQhoINGC6TLoK3ljKOg-1; Tue, 21 Feb 2023 12:55:03 -0500 X-MC-Unique: XhLrQhoINGC6TLoK3ljKOg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D0F1F2803608; Tue, 21 Feb 2023 17:55:02 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.72]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 47CC12166B26; Tue, 21 Feb 2023 17:55:00 +0000 (UTC) Date: Tue, 21 Feb 2023 17:54:57 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: John Snow Cc: Paolo Bonzini , qemu-devel , Michael Roth , Thomas Huth , Qemu-block , Cleber Rosa , Markus Armbruster , Wainer dos Santos Moschetta , Peter Maydell , Beraldo Leal , Kevin Wolf , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Hanna Reitz , Alex =?utf-8?Q?Benn=C3=A9e?= Subject: Re: [PATCH v3 1/6] configure: Look for auxiliary Python installations Message-ID: References: <20230221012456.2607692-1-jsnow@redhat.com> <20230221012456.2607692-2-jsnow@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/2.2.9 (2022-11-12) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com 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, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Tue, Feb 21, 2023 at 12:37:43PM -0500, John Snow wrote: > On Tue, Feb 21, 2023, 6:03 AM Paolo Bonzini wrote: > > > On 2/21/23 02:24, John Snow wrote: > > > At the moment, we look for just "python3" and "python", which is good > > > enough almost all of the time. But ... if you are on a platform that > > > uses an older Python by default and only offers a newer Python as an > > > option, you'll have to specify --python=/usr/bin/foo every time. > > > > > > As a courtesy, we can make a cursory attempt to locate a suitable Python > > > binary ourselves, looking for the remaining well-known binaries. This > > > also has the added benefit of making configure "just work" more often > > > on various BSD distributions that do not have the concept of a > > > "platform default python". > > > > > > This configure loop will prefer, in order: > > > > > > 1. Whatever is specified in $PYTHON > > > 2. python3 > > > 3. python (Which is usually 2.x, but might be 3.x on some platforms.) > > > 4. python3.11 down through python3.6 > > > > > > Notes: > > > > > > - Python virtual environments provide binaries for "python3", "python", > > > and whichever version you used to create the venv, > > > e.g. "python3.8". If configure is invoked from inside of a venv, this > > > configure loop will not "break out" of that venv unless that venv is > > > created using an explicitly non-suitable version of Python that we > > > cannot use. > > > > > > - In the event that no suitable python is found, the first python found > > > is the version used to generate the human-readable error message. > > > > > > - The error message isn't printed right away to allow later > > > configuration code to pick up an explicitly configured python. > > > > > > Signed-off-by: John Snow > > > --- > > > configure | 34 ++++++++++++++++++++++++++-------- > > > 1 file changed, 26 insertions(+), 8 deletions(-) > > > > > > diff --git a/configure b/configure > > > index cf6db3d5518..6abf5a72078 100755 > > > --- a/configure > > > +++ b/configure > > > @@ -592,20 +592,40 @@ esac > > > > > > : ${make=${MAKE-make}} > > > > > > -# We prefer python 3.x. A bare 'python' is traditionally > > > -# python 2.x, but some distros have it as python 3.x, so > > > -# we check that too > > > + > > > +check_py_version() { > > > + # We require python >= 3.6. > > > + # NB: a True python conditional creates a non-zero return code > > (Failure) > > > + "$1" -c 'import sys; sys.exit(sys.version_info < (3,6))' > > > +} > > > + > > > python= > > > +first_python= > > > explicit_python=no > > > -for binary in "${PYTHON-python3}" python > > > +# Check for $PYTHON, python3, python, then explicitly-versioned > > interpreters. > > > +for binary in "${PYTHON-python3}" ${PYTHON:+python3} python \ > > > + python3.11 python3.10 python3.9 \ > > > + python3.8 python3.7 python3.6 > > > > I think if PYTHON is set we shouldn't look at anything else. > > > > Paolo > > > > PYTHON is one we made up, right? $PYTHON is explicitly set in all our dockerfiles. We should ensure we honour it and not fallback to anything else when it is set. ie it would be a user error to set it to point to a python that is missing/broken, so the user should expect an error, not fallback to another version. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|