From patchwork Tue Mar 23 15:02:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Wakely X-Patchwork-Id: 1457253 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org (client-ip=2620:52:3:1:0:246e:9693:128c; helo=sourceware.org; envelope-from=gcc-patches-bounces@gcc.gnu.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=gcc.gnu.org header.i=@gcc.gnu.org header.a=rsa-sha256 header.s=default header.b=tCrCHpfm; dkim-atps=neutral Received: from sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4F4ZNc1TySz9sSC for ; Wed, 24 Mar 2021 02:02:39 +1100 (AEDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 3D62C386180A; Tue, 23 Mar 2021 15:02:35 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 3D62C386180A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1616511755; bh=PbtISEqT8T/JkUqA04EXd3B+KwKuCAtZDGorw9JTPdU=; h=Date:To:Subject:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:From; b=tCrCHpfmpxYgz6lTkWQiiyrWEWuQDs78ti+efCAvrZmRgSVY5PU9WzWqUPh+2HgWt bKr/9hlZe1m/XlU/o//Q6PNLt1UONVIhRosDesKNA67EdIECYJGjN5auRJmD8X1yaY ZI2bgh5ChVsOPB1Mhsaogo23yrXtvFnF1UuHPOgs= X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) by sourceware.org (Postfix) with ESMTP id C03863850403 for ; Tue, 23 Mar 2021 15:02:31 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org C03863850403 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-404-9FXDRx7DNQ2ks_fC4mwE1Q-1; Tue, 23 Mar 2021 11:02:25 -0400 X-MC-Unique: 9FXDRx7DNQ2ks_fC4mwE1Q-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id ED718180FCA0; Tue, 23 Mar 2021 15:02:24 +0000 (UTC) Received: from localhost (unknown [10.33.36.164]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8E9D077BE7; Tue, 23 Mar 2021 15:02:24 +0000 (UTC) Date: Tue, 23 Mar 2021 15:02:23 +0000 To: libstdc++@gcc.gnu.org, gcc-patches@gcc.gnu.org Subject: [committed] libstdc++: Disable "ALT128" long double support for Clang Message-ID: MIME-Version: 1.0 X-Clacks-Overhead: GNU Terry Pratchett X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline X-Spam-Status: No, score=-14.6 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=unavailable autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Jonathan Wakely via Gcc-patches From: Jonathan Wakely Reply-To: Jonathan Wakely Errors-To: gcc-patches-bounces@gcc.gnu.org Sender: "Gcc-patches" Clang does not currently support the __ibm128 type [1] and only supports the __ieee128 type in the unreleased 12.0.0 version [2]. That means it is not possible to provide support for -mabi=ieeelongdouble with Clang in an ABI compatible way (as we do for GCC by defining new facets and other types in the __gnu_cxx_ldbl128 namespace). By preventing the definition of _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT when compiling with Clang, all uses of __ibm128 and __ieee128 types will be disabled. This can be revisited in future when Clang supports the types (and provides a way to detect that support using the preprocessor). [1] https://reviews.llvm.org/D93377 [2] https://reviews.llvm.org/D97846 libstdc++-v3/ChangeLog: * include/bits/c++config (_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT): Do not define when compiling with Clang. Tested powerpc64le-linux. Committed to trunk. commit baef0cffb58be7f5d9aeac6313ea9d8becc017b1 Author: Jonathan Wakely Date: Tue Mar 23 13:08:32 2021 libstdc++: Disable "ALT128" long double support for Clang Clang does not currently support the __ibm128 type [1] and only supports the __ieee128 type in the unreleased 12.0.0 version [2]. That means it is not possible to provide support for -mabi=ieeelongdouble with Clang in an ABI compatible way (as we do for GCC by defining new facets and other types in the __gnu_cxx_ldbl128 namespace). By preventing the definition of _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT when compiling with Clang, all uses of __ibm128 and __ieee128 types will be disabled. This can be revisited in future when Clang supports the types (and provides a way to detect that support using the preprocessor). [1] https://reviews.llvm.org/D93377 [2] https://reviews.llvm.org/D97846 libstdc++-v3/ChangeLog: * include/bits/c++config (_GLIBCXX_LONG_DOUBLE_ALT128_COMPAT): Do not define when compiling with Clang. diff --git a/libstdc++-v3/include/bits/c++config b/libstdc++-v3/include/bits/c++config index b57ff339990..72ec91949de 100644 --- a/libstdc++-v3/include/bits/c++config +++ b/libstdc++-v3/include/bits/c++config @@ -425,9 +425,12 @@ _GLIBCXX_END_NAMESPACE_VERSION // GLIBCXX_ABI Deprecated // Define if compatibility should be provided for -mlong-double-64. #undef _GLIBCXX_LONG_DOUBLE_COMPAT + // Define if compatibility should be provided for alternative 128-bit long -// double formats. +// double formats. Not possible for Clang until __ibm128 is supported. +#ifndef __clang__ #undef _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT +#endif // Inline namespaces for long double 128 modes. #if defined _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT \