From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) by finch.gentoo.org (Postfix) with ESMTP id 58380138CC0 for ; Thu, 19 Mar 2015 04:20:45 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id A0474E08F9; Thu, 19 Mar 2015 04:20:38 +0000 (UTC) Received: from ironport2-out.teksavvy.com (ironport2-out.teksavvy.com [206.248.154.181]) by pigeon.gentoo.org (Postfix) with ESMTP id 8B978E0856 for ; Thu, 19 Mar 2015 04:20:37 +0000 (UTC) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AnQUAPOG1lRFxIfd/2dsb2JhbABbgwaBLIgGwGUEAgKBDUQBAQEBAQF8hA0BBTocMwsYCRMSDwUlN4gtziMBAQEHAgEfj38WgwCBFAWPG1SIV4ZJimOBRSKECiIxgkIBAQE X-IPAS-Result: AnQUAPOG1lRFxIfd/2dsb2JhbABbgwaBLIgGwGUEAgKBDUQBAQEBAQF8hA0BBTocMwsYCRMSDwUlN4gtziMBAQEHAgEfj38WgwCBFAWPG1SIV4ZJimOBRSKECiIxgkIBAQE X-IronPort-AV: E=Sophos;i="5.09,536,1418101200"; d="scan'208";a="113931239" Received: from 69-196-135-221.dsl.teksavvy.com (HELO waltdnes.org) ([69.196.135.221]) by ironport2-out.teksavvy.com with SMTP; 19 Mar 2015 00:20:35 -0400 Received: by waltdnes.org (sSMTP sendmail emulation); Thu, 19 Mar 2015 00:20:26 -0400 From: "Walter Dnes" Date: Thu, 19 Mar 2015 00:20:26 -0400 To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] Will a 64-bit-no-multilib machine cross-compile 32-bit code? Message-ID: <20150319042026.GA7681@waltdnes.org> References: <20150319015612.GA7416@waltdnes.org> <2685505.RfjHhG2H7t@navi> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2685505.RfjHhG2H7t@navi> User-Agent: Mutt/1.5.23 (2014-03-12) X-Archives-Salt: 6b142b3c-a954-4de0-91ca-f3a8ef186fd3 X-Archives-Hash: f22d170a8a5fcf7578c08fb7dcfc928b On Wed, Mar 18, 2015 at 10:27:05PM -0400, Fernando Rodriguez wrote > On Wednesday, March 18, 2015 9:56:12 PM Walter Dnes wrote: > > My situation... > > > > * I've dug up my ancient netbook, and got Gentoo re-installed on it > > * The cpu is a dual-core Intel(R) Atom(TM) CPU Z520 > > * It's 32-bit only; YES! > > * Compiling just the Seamonkey binary (ignoring its dependancies) took > > 14 hours > > > > I obviously want to offload compiling to another machine. As per the > > subject, will a 64-bit no-multilb install be able to cross compile > > 32-bit code? > > I've done it with distcc by adding the -m32 option to cflags. I used a script > (named after the compiler on the gentoo box) to call the compiler with the - > m32 flag and placed on the PATH environment (just for the distccd service) > before anything else and it worked. I got a 64 bit arch box to compile for a > 32 bit gentoo (not nearly as fast as compiling locally on the arch box but > much faster than the gentoo box). It should work similarly with other cross- > compile scenarios. Thanks. I'll probably be back with a bunch of questions. As a matter of fact, I already have one. The docs say that it does not work if the "-march=native" cflag is used. It says to use the output of... gcc -march=native -E -v - &1 | grep cc1 ...omitting "/usr/libexec/gcc/x86_64-pc-linux-gnu/4.8.3/cc1 -E -quiet -v -" I presume. So on the 64-bit host, I would go from... CFLAGS="-O2 -march=native -mfpmath=sse -fomit-frame-pointer -pipe -fno-unwind-tables -fno-asynchronous-unwind-tables" ...to... CFLAGS="-O2 -march=core2 -mcx16 -msahf -mno-movbe -mno-aes -mno-pclmul -mno-popcnt -mno-abm -mno-lwp -mno-fma -mno-fma4 -mno-xop -mno-bmi -mno-bmi2 -mno-tbm -mno-avx -mno-avx2 -mno-sse4.2 -mno-sse4.1 -mno-lzcnt -mno-rtm -mno-hle -mno-rdrnd -mno-f16c -mno-fsgsbase -mno-rdseed -mno-prfchw -mno-adx -mfxsr -mno-xsave -mno-xsaveopt --param l1-cache-size=32 --param l1-cache-line-size=64 --param l2-cache-size=2048 -mtune=core2 -fstack-protector -mfpmath=sse -fomit-frame-pointer -pipe -fno-unwind-tables -fno-asynchronous-unwind-tables" And on the target (netbook), I'd go to... CFLAGS="-O2 -march=atom -mno-cx16 -msahf -mmovbe -mno-aes -mno-pclmul -mno-popcnt -mno-abm -mno-lwp -mno-fma -mno-fma4 -mno-xop -mno-bmi -mno-bmi2 -mno-tbm -mno-avx -mno-avx2 -mno-sse4.2 -mno-sse4.1 -mno-lzcnt -mno-rtm -mno-hle -mno-rdrnd -mno-f16c -mno-fsgsbase -mno-rdseed -mno-prfchw -mno-adx -mfxsr -mno-xsave -mno-xsaveopt --param l1-cache-size=24 --param l1-cache-line-size=64 --param l2-cache-size=512 -mtune=atom -fstack-protector -mfpmath=sse -fomit-frame-pointer -pipe -fno-unwind-tables -fno-asynchronous-unwind-tables" Is that correct (assuming that's my output)? -- Walter Dnes I don't run "desktop environments"; I run useful applications