From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11038 invoked by alias); 9 Apr 2018 13:44:58 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 11017 invoked by uid 89); 9 Apr 2018 13:44:57 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.9 required=5.0 tests=AWL,BAYES_00 autolearn=ham version=3.3.2 spammy=reserved X-HELO: mx1.redhat.com Received: from mx3-rdu2.redhat.com (HELO mx1.redhat.com) (66.187.233.73) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 09 Apr 2018 13:44:56 +0000 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2256E4067EF0; Mon, 9 Apr 2018 13:44:55 +0000 (UTC) Received: from [127.0.0.1] (ovpn04.gateway.prod.ext.ams2.redhat.com [10.39.146.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id A19342024CA4; Mon, 9 Apr 2018 13:44:54 +0000 (UTC) Subject: Re: [PATCH v3 3/5] Add gdb::string_view To: Simon Marchi , gdb-patches@sourceware.org References: <20180407132629.3787-1-simon.marchi@polymtl.ca> <20180407132629.3787-3-simon.marchi@polymtl.ca> From: Pedro Alves Message-ID: Date: Mon, 09 Apr 2018 13:44:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180407132629.3787-3-simon.marchi@polymtl.ca> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2018-04/txt/msg00139.txt.bz2 On 04/07/2018 02:26 PM, Simon Marchi wrote: > New in v3: > > * Base on the implementation in experimental/, since it is easier to > adapt to the c++ standard we follow (c++11). I didn't see any > significant fix to import from the std/ version. > > * Tested against clang and clang+libc++ to make sure we don't rely on > anything internal and specific to libstdc++. This caught a few > issues. > > * Remove hash helpers, operator<<, operator ""sv. We can always add hash support later, but I suspect it won't be long until we will miss it, when we try to use string_view with e.g., an std::unordered_map. > * Make gdb::string_view an alias of std::string_view when building > with >= c++17. > > * Remove a bunch of constexpr, because they are not valid in c++11 > (e.g. they are not a single return line). I think I'd prefer to leave the "constexpr"'s in place, but commented out, instead of just removing it, like '/*constexpr*/', as a clearer marker that we've removed something that normally would otherwise be there, since for a future reader, simply removing is indistinguishable with missing/forgetting a constexpr. > * Remove hash helpers, because they use libstdc++ internal functions. > If we need them we always import them later. Ah, hash helpers mentioned twice. :-) Technically, the use of uglified (double-underscore or underscore-followed-by-uppercase) names is undefined behavior for being reserved to the implementation, but I think that in practice it's harmless, we should be able to deal with any conflict if it ever happens. At this stage, I think fewer local changes outweighs the very small potential for trouble. LGTM. Thanks, Pedro Alves