From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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 3F5D6385BF9E for ; Tue, 23 Mar 2021 15:02:31 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 3F5D6385BF9E 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 From: Jonathan Wakely 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-Type: multipart/mixed; boundary="1RX4DSHQ8ttvl1HS" Content-Disposition: inline X-Spam-Status: No, score=-14.1 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=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libstdc++@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libstdc++ mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 23 Mar 2021 15:02:32 -0000 --1RX4DSHQ8ttvl1HS Content-Type: text/plain; charset=us-ascii Content-Disposition: inline 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. --1RX4DSHQ8ttvl1HS Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename="patch.txt" 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 \ --1RX4DSHQ8ttvl1HS--