From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pbcl.net (pbcl.net [159.69.221.92]) by mx.groups.io with SMTP id smtpd.web10.22059.1590700280662457632 for ; Thu, 28 May 2020 14:11:21 -0700 Authentication-Results: mx.groups.io; dkim=missing; spf=pass (domain: pbcl.net, ip: 159.69.221.92, mailfrom: pb@pbcl.net) Received: from pb by pbcl.net with local (Exim 4.92) (envelope-from ) id 1jePnX-0003uw-G3; Thu, 28 May 2020 23:10:43 +0200 Date: Thu, 28 May 2020 23:10:43 +0200 From: "Phil Blundell" To: Andre McCurdy Cc: Adrian Bunk , Richard Purdie , Denys Dmytriyenko , Khem Raj , OE Core mailing list Subject: Re: [OE-core] [PATCH] linux-libc-headers: Check for asm/bpf_perf_event.h before multilibbing Message-ID: <20200528211043.GA14586@pbcl.net> References: <20200527155011.3165976-1-raj.khem@gmail.com> <20200527155957.GK17660@denix.org> <765f3daeb6ce5f28c2d1e258dd303f5707363678.camel@linuxfoundation.org> <20200527231145.GO17660@denix.org> <20200528133912.GB12536@localhost> <20200528190428.GA996@localhost> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, May 28, 2020 at 12:30:13PM -0700, Andre McCurdy wrote: > What I was trying to get at is why you felt that bringing up the fact > the kernel 4.1 was released at around the time gcc 5 was current is > important? Agreed, I think this is a red herring. One of my current targets is in fact still using Linux 4.9, which I think was roughly contemporary with GCC 6, and it still builds just fine with at least GCC 8. Although I think some of our old-timers still carry the emotional scars associated with gcc 2.8, in reality the days when a compiler upgrade ought to be expected to break the kernel in anything other than a trivial way (i.e. new warning or error that's easy to patch) are long gone. And, all that said, there is plenty of precedent for OE users keeping older versions of GCC around in order to support particular pieces of software that didn't work with newer compilers for whatever reason. It's not generally all that difficult, and anybody who was sufficiently interested could keep the old gcc version around in a separate layer even after it's deleted from oe-core. In fact oe-core did at one point even have an explicit KERNEL_CCSUFFIX variable which users could set if they wanted a specific gcc version to go with their kernel, but this was deleted in 2013 with the justification "kernel compiler is not special". p.