From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.4 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,RCVD_IN_SORBS_SPAM, RP_MATCHES_RCVD shortcircuit=no autolearn=no autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 393D62090A for ; Mon, 20 Mar 2017 20:19:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756229AbdCTUTL (ORCPT ); Mon, 20 Mar 2017 16:19:11 -0400 Received: from mail-qt0-f193.google.com ([209.85.216.193]:34454 "EHLO mail-qt0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756048AbdCTUTI (ORCPT ); Mon, 20 Mar 2017 16:19:08 -0400 Received: by mail-qt0-f193.google.com with SMTP id x35so18911224qtc.1 for ; Mon, 20 Mar 2017 13:18:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding:thread-index:content-language; bh=ZtMyZZ/4OVM/kQmuOF4H4WGx9dRUhlt+zV3HBPcDHT4=; b=XOyueZ0ixcQerlPU3k81dn8Z5C29aOvWJ0LNJtqKSO3EDwaOFEWKzDcflPEH1OV/ZW dZSKcy3B6/HULvrSpiA3Ivr+gisjEGLAxBtdGWeI+hyHUpzlsGCnOzFrRNb5UH9C6bhJ h3P3eKw9JsMAN83wE7swAoPSLyby1CtKN4NGFifHFsKEi2Z+rKPk8pYzqHOut8MGjLXE xt+TF/+zAFq5k2F3RboW+K27GVge85zDKtvcx3oTqx8oWeC8xJlNtfCC22IyFk7LEqV9 JLbNTKHrEptvKver67Y+WtP09lRrgRfOnZPGnYkzRrp6js3WXRCtR3ZfoIhg32v0BPDR wEIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding:thread-index:content-language; bh=ZtMyZZ/4OVM/kQmuOF4H4WGx9dRUhlt+zV3HBPcDHT4=; b=CB0YuV0UxSw+nYNqm89gcej5GsD47/V1lQ4Q1/iBwe6Hc5TrDJtnkGRk9AoM2N22NH g6NgvF43w2hGk+yY3aZHyVx+/ok5vzlkcIT7Y0ZlvjRA7Y84BhfMKENGQxBOG/ioCWop D4qpc9PN3R6E47BKcEWVVXXwpPMfLjNruUSc99HT/cuqIMuIV5xkKYvnEkihHqxuAgdN maDGu+A6aLfUV4bX0nz08ruUJa58Ccf4bujIS0Ku9Wip2O5l5uz7UNj5VUVgxkualVKj 7/1YuY6x/XtuRSgYL4LUc8sdSapocDLqWiAyLrzhUHpoF7/ZTu2QctvzubwLmP+mfhAx X3dA== X-Gm-Message-State: AFeK/H2GBSouI/sDlcoeYl5e36WpmpuIihKnWuUPvqfednjZgURz+hgHVZi7+pPjkkWSnA== X-Received: by 10.200.51.92 with SMTP id u28mr30622083qta.151.1490041101124; Mon, 20 Mar 2017 13:18:21 -0700 (PDT) Received: from BenPeartHP ([65.222.173.206]) by smtp.gmail.com with ESMTPSA id n84sm13155787qki.42.2017.03.20.13.18.19 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 20 Mar 2017 13:18:20 -0700 (PDT) From: "Ben Peart" To: "'git'" Cc: "Jeff Hostetler \(jeffhost@microsoft.com\)" , "Ben Peart" Subject: Safe to use stdatomic.h? Date: Mon, 20 Mar 2017 16:18:20 -0400 Message-ID: <000801d2a1b7$1ec41620$5c4c4260$@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 16.0 Thread-Index: AdKhtiqZ4jbgVZRzQeeUIKbnh6RzBA== Content-Language: en-us Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org My college Jeff is working on a patch series to further parallelize the loading of the index. As part of that patch, it would be nice to use the atomic_fetch_add function as that would be more efficient than creating a mutex simply to protect a variable so that it can be incremented. I haven't seen any use of atomics yet in Git, nor anything that includes . GCC has supported them since 4.9 and Clang has supported them by default since 3.3. Are there any compilers currently in use by Git that don't support these C11 functions? Thanks, Ben