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 53FBD3858C62 for ; Fri, 20 Jan 2023 02:03:47 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 53FBD3858C62 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1674180227; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=GFee3gbBBwGz3IflVgCmbjJ4XxESyj2lgUSXcS0Rsj4=; b=fYwK5qT0YFOuHLXoRqAnHn/v7spaOB5f5HyQA1P4ta8rHav3SER9T0ySPlYUeBsnO41YnE HkjdxcQuhABnFc/5MefwMTVXuA29kyjqhd8UE0hq3gfzKYkuOe+Jxz3Gw2Eda6/AGuc1O0 xftfPq2gQxSUM9Xjm4CVKiPqgSc93Ic= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-423-IrPXZrIpNc6-iSQeQ020Ug-1; Thu, 19 Jan 2023 21:03:45 -0500 X-MC-Unique: IrPXZrIpNc6-iSQeQ020Ug-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 39C17800B30 for ; Fri, 20 Jan 2023 02:03:45 +0000 (UTC) Received: from pdp-11.redhat.com (unknown [10.22.33.5]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1CCAE2166B2A; Fri, 20 Jan 2023 02:03:45 +0000 (UTC) From: Marek Polacek To: Jason Merrill , GCC Patches Subject: [PATCH] c++: Quash bogus -Wunused-value with new [PR107797] Date: Thu, 19 Jan 2023 21:03:39 -0500 Message-Id: <20230120020339.1025075-1-polacek@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII"; x-default=true X-Spam-Status: No, score=-12.1 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_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: We shouldn't emit "right operand of comma operator has no effect" when that comma operator was created by the compiler for "new int{}". convert_to_void/COMPOUND_EXPR already checks warning_suppressed_p so we can just suppress -Wunused-value. Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? PR c++/107797 gcc/cp/ChangeLog: * cvt.cc (ocp_convert): copy_warning when creating a new COMPOUND_EXPR. * init.cc (build_new_1): Suppress -Wunused-value on compiler-generated COMPOUND_EXPRs. gcc/testsuite/ChangeLog: * g++.dg/warn/Wunused-value-1.C: New test. --- gcc/cp/cvt.cc | 6 ++++-- gcc/cp/init.cc | 2 ++ gcc/testsuite/g++.dg/warn/Wunused-value-1.C | 12 ++++++++++++ 3 files changed, 18 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/g++.dg/warn/Wunused-value-1.C diff --git a/gcc/cp/cvt.cc b/gcc/cp/cvt.cc index 0cbfd8060cb..17827d06a4a 100644 --- a/gcc/cp/cvt.cc +++ b/gcc/cp/cvt.cc @@ -711,8 +711,10 @@ ocp_convert (tree type, tree expr, int convtype, int flags, return error_mark_node; if (e == TREE_OPERAND (expr, 1)) return expr; - return build2_loc (EXPR_LOCATION (expr), COMPOUND_EXPR, TREE_TYPE (e), - TREE_OPERAND (expr, 0), e); + e = build2_loc (EXPR_LOCATION (expr), COMPOUND_EXPR, TREE_TYPE (e), + TREE_OPERAND (expr, 0), e); + copy_warning (e, expr); + return e; } complete_type (type); diff --git a/gcc/cp/init.cc b/gcc/cp/init.cc index f816c474cef..52e96fbe590 100644 --- a/gcc/cp/init.cc +++ b/gcc/cp/init.cc @@ -3800,6 +3800,8 @@ build_new_1 (vec **placement, tree type, tree nelts, if (cookie_expr) rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), cookie_expr, rval); + suppress_warning (rval, OPT_Wunused_value); + if (rval == data_addr && TREE_CODE (alloc_expr) == TARGET_EXPR) /* If we don't have an initializer or a cookie, strip the TARGET_EXPR and return the call (which doesn't need to be adjusted). */ diff --git a/gcc/testsuite/g++.dg/warn/Wunused-value-1.C b/gcc/testsuite/g++.dg/warn/Wunused-value-1.C new file mode 100644 index 00000000000..2ba5587fce0 --- /dev/null +++ b/gcc/testsuite/g++.dg/warn/Wunused-value-1.C @@ -0,0 +1,12 @@ +// PR c++/107797 +// { dg-do compile { target c++11 } } +// { dg-options "-Wunused" } + +void +g () +{ + (long) new int{}; + long(new int{}); + (long) new int(); + long(new int()); +} base-commit: 86caab6c5d1e26e1c54c3dceacc873d6e27bfc09 -- 2.39.0