From patchwork Sun Oct 3 19:48:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Iain Sandoe X-Patchwork-Id: 1535875 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.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=os20PORR; dkim-atps=neutral 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+incoming=patchwork.ozlabs.org@gcc.gnu.org; receiver=) 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 bilbo.ozlabs.org (Postfix) with ESMTPS id 4HMvYD5G9nz9t0G for ; Mon, 4 Oct 2021 06:48:48 +1100 (AEDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id A7C46385700C for ; Sun, 3 Oct 2021 19:48:45 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org A7C46385700C DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1633290525; bh=Btf5FjJD6oRyNCoqpqthlHh+wRKkPvLfiZuAsTqubzQ=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:Cc:From; b=os20PORR2KdgqHewGD1MbVB7AGgNVgHQiWXiU6AGsdWjcTuE4NKOfeP0TNRe3r7rM z4VtptxecNFtreK687zIjCyUtzQjPxJ9F6Zp484K096wsr47JRnDydXvar8al8SkNU OOZQFhe5+HdD4Tr3Ovl2YON1lmImFVzOCYvlta24= X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from mail-wr1-x433.google.com (mail-wr1-x433.google.com [IPv6:2a00:1450:4864:20::433]) by sourceware.org (Postfix) with ESMTPS id 157F53858D39 for ; Sun, 3 Oct 2021 19:48:25 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 157F53858D39 Received: by mail-wr1-x433.google.com with SMTP id o20so8464025wro.3 for ; Sun, 03 Oct 2021 12:48:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :mime-version:content-transfer-encoding; bh=Btf5FjJD6oRyNCoqpqthlHh+wRKkPvLfiZuAsTqubzQ=; b=ilXC3bJLA5i+VYKTiM+XLGSv3gDAlUq3i8dxUS8tTEMOy9/qF44c+mnyf7YVIqATgF DRiOPpbFrRvwGcuHmiUKrJlI45moFJp8ROrdxYor6YVet34qbePJ50TVm0MaHKXwyDlR yVawUeKvmSVeIq9BvfnhGQ0MQvoC4E0SpAZibGWM1bEFh4PWYwA3CqDhw7ahgabFyfom PEHickBqhu2C3xQdQ7oXlhl4k8o6ad6rJD8YHtlekW6vqa5KGCUtdF0NnDqQKTWs//fz nrZ3rXAOjyiIH8+kWjiEyjNJA0SP7YzkLtKQbN2JTEBNa5pScSUnOVKBcNYVPF5HXPwF tM/A== X-Gm-Message-State: AOAM5320QA8MsYyY29FUhB12efPn15uE8QBwa0HXdsgnmERmY2nKy70+ XYyKaVE/JJmhtcrZJHvg9YLSSfba66X33Q== X-Google-Smtp-Source: ABdhPJzWsT5ddjPYWVIgayjyBA4p2S3BJRH4ZcvsGQE8E0a3rjS8I6qBeWTCqnnAMIEVonNHZiAQFw== X-Received: by 2002:a5d:453b:: with SMTP id j27mr10140630wra.324.1633290504142; Sun, 03 Oct 2021 12:48:24 -0700 (PDT) Received: from localhost.localdomain (host81-138-1-83.in-addr.btopenworld.com. [81.138.1.83]) by smtp.gmail.com with ESMTPSA id c5sm2170601wml.9.2021.10.03.12.48.23 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sun, 03 Oct 2021 12:48:23 -0700 (PDT) X-Google-Original-From: Iain Sandoe To: gcc-patches@gcc.gnu.org Subject: [PATCH] coroutines: Ensure co_await_exprs have TREE_SIDE_EFFECTS set [PR 101133]. Date: Sun, 3 Oct 2021 20:48:17 +0100 Message-Id: <20211003194817.67417-1-iain@sandoe.co.uk> X-Mailer: git-send-email 2.24.3 (Apple Git-128) MIME-Version: 1.0 X-Spam-Status: No, score=-8.5 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, 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-Patchwork-Original-From: Iain Sandoe via Gcc-patches From: Iain Sandoe Reply-To: iain@sandoe.co.uk Cc: Iain Sandoe Errors-To: gcc-patches-bounces+incoming=patchwork.ozlabs.org@gcc.gnu.org Sender: "Gcc-patches" Hi, Although it is not immediately evident from the symptoms, the PR is caused by a variable having a DECL_INITIAL() containing a co_await. This is not correct, since such expressions have side-effects. We were marking the overall co_await expression correctly, but if a consumer of that expression stripped out the underlying co_await_expr then the latter would not be properly marked. Fixed by marking both the underlying and any containing await expr with TREE_SIDE_EFFECTS. Also mark type-dependent co_await expressions. tested on x86_64, powerpc64le linux and x86_64 darwin, pushed to master as obvious, thanks, Iain Signed-off-by: Iain Sandoe PR c++/101133 gcc/cp/ChangeLog: * coroutines.cc (build_co_await): Mark co_await_expr trees with TREE_SIDE_EFFECTS, also mark any containing expression. (finish_co_await_expr): Mark type-dependent co_await_expr trees with TREE_SIDE_EFFECTS. gcc/testsuite/ChangeLog: * g++.dg/coroutines/pr101133.C: New test. --- gcc/cp/coroutines.cc | 24 ++++++++--------- gcc/testsuite/g++.dg/coroutines/pr101133.C | 31 ++++++++++++++++++++++ 2 files changed, 43 insertions(+), 12 deletions(-) create mode 100644 gcc/testsuite/g++.dg/coroutines/pr101133.C diff --git a/gcc/cp/coroutines.cc b/gcc/cp/coroutines.cc index 876a14606f8..bff5b6343e5 100644 --- a/gcc/cp/coroutines.cc +++ b/gcc/cp/coroutines.cc @@ -1117,13 +1117,15 @@ build_co_await (location_t loc, tree a, suspend_point_kind suspend_kind) a, e_proxy, o, awaiter_calls, build_int_cst (integer_type_node, (int) suspend_kind)); + TREE_SIDE_EFFECTS (await_expr) = true; if (te) { TREE_OPERAND (te, 1) = await_expr; + TREE_SIDE_EFFECTS (te) = true; await_expr = te; } - tree t = convert_from_reference (await_expr); - return t; + SET_EXPR_LOCATION (await_expr, loc); + return convert_from_reference (await_expr); } tree @@ -1149,8 +1151,13 @@ finish_co_await_expr (location_t kw, tree expr) co_await with the expression unchanged. */ tree functype = TREE_TYPE (current_function_decl); if (dependent_type_p (functype) || type_dependent_expression_p (expr)) - return build5_loc (kw, CO_AWAIT_EXPR, unknown_type_node, expr, - NULL_TREE, NULL_TREE, NULL_TREE, integer_zero_node); + { + tree aw_expr = build5_loc (kw, CO_AWAIT_EXPR, unknown_type_node, expr, + NULL_TREE, NULL_TREE, NULL_TREE, + integer_zero_node); + TREE_SIDE_EFFECTS (aw_expr) = true; + return aw_expr; + } /* We must be able to look up the "await_transform" method in the scope of the promise type, and obtain its return type. */ @@ -1187,14 +1194,7 @@ finish_co_await_expr (location_t kw, tree expr) } /* Now we want to build co_await a. */ - tree op = build_co_await (kw, a, CO_AWAIT_SUSPEND_POINT); - if (op != error_mark_node) - { - TREE_SIDE_EFFECTS (op) = 1; - SET_EXPR_LOCATION (op, kw); - } - - return op; + return build_co_await (kw, a, CO_AWAIT_SUSPEND_POINT); } /* Take the EXPR given and attempt to build: diff --git a/gcc/testsuite/g++.dg/coroutines/pr101133.C b/gcc/testsuite/g++.dg/coroutines/pr101133.C new file mode 100644 index 00000000000..6c6bc163251 --- /dev/null +++ b/gcc/testsuite/g++.dg/coroutines/pr101133.C @@ -0,0 +1,31 @@ +#include +#include + +template +struct Awaiter +{ + bool await_ready() const { return false; } + void await_suspend(std::coroutine_handle<>) const {} + T await_resume() const { return T{}; } +}; + +struct ReturnObject +{ + struct promise_type + { + ReturnObject get_return_object() { return {}; } + std::suspend_never initial_suspend() noexcept { return {}; } + std::suspend_never final_suspend() noexcept { return {}; } + void return_void() {} + void unhandled_exception() {} + }; +}; + +ReturnObject f() +{ + auto a1 = Awaiter{}; + auto a2 = Awaiter{}; + + [[maybe_unused]] auto v1 = co_await a1; // ok + [[maybe_unused]] std::string v2 = co_await a2; // error +}