From owner-svn-src-all@freebsd.org Fri Jan 19 18:43:52 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 258C5EC168F; Fri, 19 Jan 2018 18:43:52 +0000 (UTC) (envelope-from freebsd@pdx.rh.CN85.dnsmgr.net) Received: from pdx.rh.CN85.dnsmgr.net (br1.CN84in.dnsmgr.net [69.59.192.140]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 03B0A6EAA4; Fri, 19 Jan 2018 18:43:51 +0000 (UTC) (envelope-from freebsd@pdx.rh.CN85.dnsmgr.net) Received: from pdx.rh.CN85.dnsmgr.net (localhost [127.0.0.1]) by pdx.rh.CN85.dnsmgr.net (8.13.3/8.13.3) with ESMTP id w0JIhoAQ073409; Fri, 19 Jan 2018 10:43:50 -0800 (PST) (envelope-from freebsd@pdx.rh.CN85.dnsmgr.net) Received: (from freebsd@localhost) by pdx.rh.CN85.dnsmgr.net (8.13.3/8.13.3/Submit) id w0JIhoVS073408; Fri, 19 Jan 2018 10:43:50 -0800 (PST) (envelope-from freebsd) From: "Rodney W. Grimes" Message-Id: <201801191843.w0JIhoVS073408@pdx.rh.CN85.dnsmgr.net> Subject: Re: svn commit: r328159 - head/sys/modules In-Reply-To: To: cem@freebsd.org Date: Fri, 19 Jan 2018 10:43:50 -0800 (PST) CC: John Baldwin , src-committers , svn-src-all@freebsd.org, svn-src-head@freebsd.org Reply-To: rgrimes@freebsd.org X-Mailer: ELM [version 2.4ME+ PL121h (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 19 Jan 2018 18:43:52 -0000 [ Charset UTF-8 unsupported, converting... ] > On Fri, Jan 19, 2018 at 9:51 AM, John Baldwin wrote: > > On Friday, January 19, 2018 04:34:06 AM Conrad Meyer wrote: > >> The logical result of a right shift >= the width of a type is zero, but our > >> compiler decides this is a warning (and thus, error). Just remove ccp(4) > >> from i386. > > > > You would think that. The shift instructions on x86 effectively ignore the > > upper bits of the count, so a 33-bit shift on i386 ends up being a 1-bit shift, > > etc. IIRC. > > This never becomes a shift instruction on x86 or any other arch ? it's > a constant before it reaches machine code. A constant that is produce by a? Shift insturction perhaps? Ok, that was pedantically over kill, but is what most likely happens. -- Rod Grimes rgrimes@freebsd.org