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 [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id B91E23858039 for ; Fri, 28 Jan 2022 01:02:21 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org B91E23858039 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-659-R29AglebPkKDYTUi-sF2pw-1; Thu, 27 Jan 2022 20:02:19 -0500 X-MC-Unique: R29AglebPkKDYTUi-sF2pw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 64D242F46 for ; Fri, 28 Jan 2022 01:02:18 +0000 (UTC) Received: from pdp-11.hsd1.ma.comcast.net (unknown [10.22.33.73]) by smtp.corp.redhat.com (Postfix) with ESMTP id BDFA560BD8; Fri, 28 Jan 2022 01:02:14 +0000 (UTC) From: Marek Polacek To: GCC Patches , Jason Merrill Subject: [PATCH] c++: ICE with auto[] and VLA [PR102414] Date: Thu, 27 Jan 2022 20:02:09 -0500 Message-Id: <20220128010209.586323-1-polacek@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" X-Spam-Status: No, score=-13.8 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_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) 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-List-Received-Date: Fri, 28 Jan 2022 01:02:23 -0000 Here we ICE in unify_array_domain when we're trying to deduce the type of an array, as in auto(*p)[i] = (int(*)[i])0; but unify_array_domain doesn't arbitrarily complex bounds. Another test is, e.g., auto (*b)[0/0] = &a; where the type of the array is <<< Unknown tree: template_type_parm >>>[0:(sizetype) ((ssizetype) (0 / 0) - 1)] It seems to me that we need not handle these. Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? PR c++/102414 PR c++/101874 gcc/cp/ChangeLog: * decl.cc (create_array_type_for_decl): Use template_placeholder_p. Sorry on a variable-length array of auto. gcc/testsuite/ChangeLog: * g++.dg/cpp23/auto-array3.C: New test. * g++.dg/cpp23/auto-array4.C: New test. --- gcc/cp/decl.cc | 14 +++++++++++--- gcc/testsuite/g++.dg/cpp23/auto-array3.C | 17 +++++++++++++++++ gcc/testsuite/g++.dg/cpp23/auto-array4.C | 10 ++++++++++ 3 files changed, 38 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp23/auto-array3.C create mode 100644 gcc/testsuite/g++.dg/cpp23/auto-array4.C diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc index 10e6956117e..4ba8bf3e8a9 100644 --- a/gcc/cp/decl.cc +++ b/gcc/cp/decl.cc @@ -11089,7 +11089,7 @@ create_array_type_for_decl (tree name, tree type, tree size, location_t loc) /* [dcl.type.class.deduct] prohibits forming an array of placeholder for a deduced class type. */ - if (is_auto (type) && CLASS_PLACEHOLDER_TEMPLATE (type)) + if (template_placeholder_p (type)) { if (name) error_at (loc, "%qD declared as array of template placeholder " @@ -11159,8 +11159,16 @@ create_array_type_for_decl (tree name, tree type, tree size, location_t loc) /* Figure out the index type for the array. */ if (size) - itype = compute_array_index_type_loc (loc, name, size, - tf_warning_or_error); + { + itype = compute_array_index_type_loc (loc, name, size, + tf_warning_or_error); + if (type_uses_auto (type) + && !TREE_CONSTANT (maybe_constant_value (size))) + { + sorry_at (loc, "variable-length array of %"); + return error_mark_node; + } + } return build_cplus_array_type (type, itype); } diff --git a/gcc/testsuite/g++.dg/cpp23/auto-array3.C b/gcc/testsuite/g++.dg/cpp23/auto-array3.C new file mode 100644 index 00000000000..e383a17d0ee --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp23/auto-array3.C @@ -0,0 +1,17 @@ +// PR c++/102414 +// { dg-do compile { target c++11 } } +// { dg-options "" } + +constexpr int sz () { return 3; } + +void f () +{ + int a[3]; + auto (*a1)[0/0] = &a; // { dg-message "variable-length array of .auto." } +// { dg-warning "division by zero" "" { target *-*-* } .-1 } + const int N = 3; + auto (*a2)[N] = &a; + constexpr int M = 3; + auto (*a3)[M] = &a; + auto (*a4)[sz()] = &a; +} diff --git a/gcc/testsuite/g++.dg/cpp23/auto-array4.C b/gcc/testsuite/g++.dg/cpp23/auto-array4.C new file mode 100644 index 00000000000..4819472a9ac --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp23/auto-array4.C @@ -0,0 +1,10 @@ +// PR c++/101874 +// { dg-do compile { target c++11 } } +// { dg-options "" } + +void +f (int i) +{ + auto x[i] = { 0 }; // { dg-message "variable-length array of .auto." } + auto(*p)[i] = (int(*)[i])0; // { dg-message "variable-length array of .auto." } +} base-commit: 99f17e996f21d0ed64c36ed1e52977b705143522 -- 2.34.1