From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1S9gL3-0004iN-9e for garchives@archives.gentoo.org; Mon, 19 Mar 2012 17:25:45 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 28EEDE08E0; Mon, 19 Mar 2012 17:25:21 +0000 (UTC) Received: from mail5.tpgi.com.au (mail5.tpgi.com.au [203.12.160.101]) by pigeon.gentoo.org (Postfix) with ESMTP id 25CBCE0DD3 for ; Mon, 19 Mar 2012 17:24:11 +0000 (UTC) X-TPG-Junk-Checked: Yes X-TPG-Junk-Status: Message not scanned because user authenticated using SMTP AUTH X-TPG-Antivirus: Passed X-TPG-Abuse: host=27-33-235-192.static.tpgi.com.au; ip=27.33.235.192; date=Tue, 20 Mar 2012 04:24:09 +1100; auth=uvyrE+o6fAwqkkuYeCaT6kEOJM7fAGbLpPpVerb0wHQ= Received: from [192.168.14.2] (27-33-235-192.static.tpgi.com.au [27.33.235.192]) (authenticated bits=0) by mail5.tpgi.com.au (envelope-from agl@wht.com.au) (8.14.3/8.14.3) with ESMTP id q2JHO6NM010840 for ; Tue, 20 Mar 2012 04:24:09 +1100 Message-ID: <4F676BB6.1070804@wht.com.au> Date: Tue, 20 Mar 2012 01:24:06 +0800 From: Andrew Lowe Organization: Wombat High Tech User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.1) Gecko/20120307 Thunderbird/10.0.1 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 To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] Re: Changing compilers References: <20120319132643.Horde.NzbZHrtUV7tPZsOT40nUZ2A@webmail.wht.com.au> <4F673E98.4070907@wht.com.au> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Archives-Salt: 415298a0-822c-4330-8613-e137bc89a22e X-Archives-Hash: c5e10eb67cc4bf4dc5eb8f3745a36d82 On 03/20/12 01:17, Nikos Chantziaras wrote: > On 19/03/12 16:11, Andrew Lowe wrote: >> On 03/19/12 17:39, Nikos Chantziaras wrote: >>> On 19/03/12 07:26, Andrew Lowe wrote: >>>> Hi all, >>>> Has anyone played around with the various "better known" compilers on >> [snip] >> ... >> ... >> [snip] >>> >>> You don't need to "change" compilers. You can use whatever one you like >>> to build your program. The compiler portage uses to build its packages >>> does not affect your own usage of the others. >>> >>> As for the fastest one, I can only speak for Intel CPUs where Intel C++ >>> gives me the fastest binaries. >>> >>> >>> >> Nikos, >> Your experience with Intel is what I'm after. Aster, the FEA code I'm >> going to use is not in Portage hence I will be using it's own build >> system. When you've used Intel, have you just exported "CC="icc" or >> something similar, as make.conf won't be used? Also, I've read somewhere >> that there are libraries that you have to link against that are specific >> to the Intel compiler as it does not create libraries that are >> comparable with the gcc produced ones - is this true or does the >> compiler now "play well" with the gcc world? > > No special libs required. The binaries I get (both C and C++) don't use > anything extra. I checked both with "ldd" as well as with lsof at > runtime (in case it dlopens anything). > > For building, you use "CC=icc" and "CXX=icpc" for regular makefiles or > autoconf scripts. I mostly use qmake though (I use Qt for my GUIs). In > that case, you call qmake like this: > > qmake -spec linux-icc > > and it creates a makefile that will use ICC. This is also an example of > ICC using C and C++ libs (Qt is C++) that were built by GCC without > issues; its ABI is fully GCC compatible. > > There are way to use ICC for portage too. I tried that once. It worked > quite well. But I didn't went with it since too much of a bother. > > Note that the link Florian posted is a bit outdated. For example the > sections that tells you that "binaries compiled with icc won't work > after icc is uninstalled" is not true. They will work just fine. The > exception of course if when you specifically use an ICC library, like > the Intel math kernel library. > > > Thanks for that. The library question was the reason I didn't proceed with playing around with icc ages ago. Your experience tells me it's now rectified. Andrew