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GET /api/1.1/patches/2223531/?format=api
{ "id": 2223531, "url": "http://patchwork.ozlabs.org/api/1.1/patches/2223531/?format=api", "web_url": "http://patchwork.ozlabs.org/project/gcc/patch/20260415140454.2345899-1-jason@redhat.com/", "project": { "id": 17, "url": "http://patchwork.ozlabs.org/api/1.1/projects/17/?format=api", "name": "GNU Compiler Collection", "link_name": "gcc", "list_id": "gcc-patches.gcc.gnu.org", "list_email": "gcc-patches@gcc.gnu.org", "web_url": null, "scm_url": null, "webscm_url": null }, "msgid": "<20260415140454.2345899-1-jason@redhat.com>", "date": "2026-04-15T14:02:09", "name": "c++: unusual await_suspend parameters [PR123975]", "commit_ref": null, "pull_url": null, "state": "new", "archived": false, "hash": "e8391f7bad2915309bc4561c330bba58caa15761", "submitter": { "id": 4337, "url": "http://patchwork.ozlabs.org/api/1.1/people/4337/?format=api", "name": "Jason Merrill", "email": "jason@redhat.com" }, "delegate": null, "mbox": "http://patchwork.ozlabs.org/project/gcc/patch/20260415140454.2345899-1-jason@redhat.com/mbox/", "series": [ { "id": 499992, "url": "http://patchwork.ozlabs.org/api/1.1/series/499992/?format=api", "web_url": "http://patchwork.ozlabs.org/project/gcc/list/?series=499992", "date": "2026-04-15T14:02:09", "name": "c++: unusual await_suspend parameters [PR123975]", "version": 1, "mbox": "http://patchwork.ozlabs.org/series/499992/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/patches/2223531/comments/", "check": "pending", "checks": "http://patchwork.ozlabs.org/api/patches/2223531/checks/", "tags": {}, "headers": { "Return-Path": "<gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "gcc-patches@gcc.gnu.org" ], "Delivered-To": [ "patchwork-incoming@legolas.ozlabs.org", "gcc-patches@gcc.gnu.org" ], "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=mimecast20190719 header.b=KiJZidIv;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org\n (client-ip=2620:52:6:3111::32; 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Wed, 15 Apr 2026 14:04:55 +0000 (UTC)" ], "DKIM-Filter": [ "OpenDKIM Filter v2.11.0 sourceware.org E90814BA2E14", "OpenDKIM Filter v2.11.0 sourceware.org 41ACA4BA2E09" ], "DMARC-Filter": "OpenDMARC Filter v1.4.2 sourceware.org 41ACA4BA2E09", "ARC-Filter": "OpenARC Filter v1.0.0 sourceware.org 41ACA4BA2E09", "ARC-Seal": "i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1776261903; cv=none;\n b=wQd0CMy7aDNdACSBLkQrgX2CA4o7DhSNKQPhF1W43ZV9aHuB6YqbNupgGfXI/SHNN9l0volToq5PmT39xs0FoUzb8CAfl1jTtEMkLn8UW9giyy0FURyQNmmgX1XciUvdoNpO/anMic08+50PHsp9nCLBL7bSGzNksloovucr9RU=", "ARC-Message-Signature": "i=1; a=rsa-sha256; d=sourceware.org; s=key;\n t=1776261903; c=relaxed/simple;\n bh=MW/f1Q8IG7he62uauJJnXNdcb+2sRMvRjK7yuhMcJTM=;\n h=DKIM-Signature:From:To:Subject:Date:Message-ID:MIME-Version;\n b=FvFM4cQPqDKiOhG6WCCJtekofL/htPaABnbI7CtCXihb8KWA8zWusLHqxjOOWo6Mn/WEuxLWEYVZop4BjfkTYP4+v+w1eSFpL53WRSdOo2WOWFT/Ar/wBHl8+i/bkI3DCVMGC6/r11fb6h3auZbedcH0UgnfnTDrjn4UgSrGwaY=", "ARC-Authentication-Results": "i=1; server2.sourceware.org", "DKIM-Signature": "v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;\n s=mimecast20190719; t=1776261903;\n h=from:from:reply-to:subject:subject:date:date:message-id:message-id:\n to:to:cc:cc:mime-version:mime-version:content-type:content-type:\n content-transfer-encoding:content-transfer-encoding;\n bh=cfQj4GmGOOy2hsWjqua2ZQPUsSJK4tkW4bWQrahfTfg=;\n b=KiJZidIv+PxuuK+SYbK5guB2MiBYMMEi0WT0WHCswTd/VX8MgdQjDDlMUn7+1ER+pl79Yj\n qVlDoBQ60CpQswG/4zfnyU7gKyYDgE8AswY7AvQYGjohzm3Orei9K0Ak/fzFjBZZ+hsVmz\n rNVEEnwPZfUjI2NgNh5oBDuyFYvweXM=", "X-MC-Unique": "wW-2_gEHMhqlzRPxEXGLgQ-1", "X-Mimecast-MFC-AGG-ID": "wW-2_gEHMhqlzRPxEXGLgQ_1776261896", "From": "Jason Merrill <jason@redhat.com>", "To": "gcc-patches@gcc.gnu.org,\n\tDavid Malcolm <dmalcolm@redhat.com>", "Cc": "Iain Sandoe <iain@sandoe.co.uk>", "Subject": "[PATCH] c++: unusual await_suspend parameters [PR123975]", "Date": "Wed, 15 Apr 2026 10:02:09 -0400", "Message-ID": "<20260415140454.2345899-1-jason@redhat.com>", "MIME-Version": "1.0", "X-Scanned-By": "MIMEDefang 3.4.1 on 10.30.177.4", "X-Mimecast-Spam-Score": "0", "X-Mimecast-MFC-PROC-ID": "VRgu8yQsteBxUs4QMRkh0fK8PcwBz2iR8JwcxLE9Lk4_1776261896", "X-Mimecast-Originator": "redhat.com", "Content-Transfer-Encoding": "8bit", "content-type": "text/plain; charset=\"US-ASCII\"; x-default=true", "X-BeenThere": "gcc-patches@gcc.gnu.org", "X-Mailman-Version": "2.1.30", "Precedence": "list", "List-Id": "Gcc-patches mailing list <gcc-patches.gcc.gnu.org>", "List-Unsubscribe": "<https://gcc.gnu.org/mailman/options/gcc-patches>,\n <mailto:gcc-patches-request@gcc.gnu.org?subject=unsubscribe>", "List-Archive": "<https://gcc.gnu.org/pipermail/gcc-patches/>", "List-Post": "<mailto:gcc-patches@gcc.gnu.org>", "List-Help": "<mailto:gcc-patches-request@gcc.gnu.org?subject=help>", "List-Subscribe": "<https://gcc.gnu.org/mailman/listinfo/gcc-patches>,\n <mailto:gcc-patches-request@gcc.gnu.org?subject=subscribe>", "Errors-To": "gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org" }, "content": "Tested x86_64-pc-linux-gnu, applying to trunk.\n\nDavid, do you agree with just adding dg-excess-errors to the analyzer ICE\ntestcase, or do you want to investigate the new false positive?\n\n-- 8< --\n\nexpand_one_await_expression was assuming we could replace the last argument\nof await_suspend with a call to handle::from_address. This is wrong if\neither the handle parameter has a different type (123975) or await_suspend\nhas additional parameters (121643).\n\nThe change to pr105287.C is needed because that test now correctly calls\noperator coroutine_handle<>(), and that addition confuses the analyzer into\nthinking there's a use-after-free problem. Since the analyzer is known to\nhave a lot of trouble with coroutines (PR105382), let's ignore the new false\npositive and just check that the test doesn't ICE.\n\n\tPR c++/121643\n\tPR c++/123975\n\ngcc/cp/ChangeLog:\n\n\t* coroutines.cc (build_co_await): Pass rvalue to await_suspend.\n\t(expand_one_await_expression): Fix await_suspend surgery.\n\ngcc/testsuite/ChangeLog:\n\n\t* g++.dg/coroutines/pr105287.C: Add dg-excess-errors.\n\t* g++.dg/coroutines/pr121643.C: New test.\n\t* g++.dg/coroutines/pr123975.C: New test.\n---\n gcc/cp/coroutines.cc | 16 ++++++-\n gcc/testsuite/g++.dg/coroutines/pr105287.C | 2 +\n gcc/testsuite/g++.dg/coroutines/pr121643.C | 29 ++++++++++++\n gcc/testsuite/g++.dg/coroutines/pr123975.C | 52 ++++++++++++++++++++++\n 4 files changed, 98 insertions(+), 1 deletion(-)\n create mode 100644 gcc/testsuite/g++.dg/coroutines/pr121643.C\n create mode 100644 gcc/testsuite/g++.dg/coroutines/pr123975.C\n\n\nbase-commit: 215cc0d494746ca80ef1c9d2f4a8930983070714", "diff": "diff --git a/gcc/cp/coroutines.cc b/gcc/cp/coroutines.cc\nindex f9fbffa60b3..6bc58a4f2e6 100644\n--- a/gcc/cp/coroutines.cc\n+++ b/gcc/cp/coroutines.cc\n@@ -1471,6 +1471,9 @@ build_co_await (location_t loc, tree a, suspend_point_kind suspend_kind,\n 3. a coroutine handle, we execute the handle.resume() call. */\n tree awsp_func = NULL_TREE;\n tree h_proxy = get_coroutine_self_handle_proxy (current_function_decl);\n+ /* expand_one_await_expression will replace the argument with a prvalue call\n+ to from_address, so pass an rvalue now as well. */\n+ h_proxy = move (h_proxy);\n vec<tree, va_gc> *args = make_tree_vector_single (h_proxy);\n tree awsp_call\n = build_new_method_call (e_proxy, awsp_meth, &args, NULL_TREE,\n@@ -2237,7 +2240,18 @@ expand_one_await_expression (tree *expr, tree *await_expr, void *d)\n build_new_method_call (dummy_ch, data->hfa_m, &args, NULL_TREE,\n \t\t\t LOOKUP_NORMAL, NULL, tf_warning_or_error));\n release_tree_vector (args);\n- CALL_EXPR_ARG (susp_call, call_expr_nargs (susp_call) - 1) = hfa;\n+ {\n+ tree fn = get_callee_fndecl (susp_call);\n+ int argno = 0 + DECL_OBJECT_MEMBER_FUNCTION_P (fn);\n+ tree &arg = CALL_EXPR_ARG (susp_call, argno);\n+ /* Handle await_suspend taking an unusual type (c++/123975). */\n+ tree type = TYPE_ARG_TYPES (TREE_TYPE (fn));\n+ type = TREE_VALUE (chain_index (argno, type));\n+ hfa = perform_implicit_conversion (type, hfa, tf_warning_or_error);\n+ hfa = convert_for_arg_passing (type, hfa, tf_warning_or_error);\n+ gcc_checking_assert (same_type_p (TREE_TYPE (arg), TREE_TYPE (hfa)));\n+ arg = hfa;\n+ }\n \n bool is_cont = false;\n /* NOTE: final suspend can't resume; the \"resume\" label in that case\ndiff --git a/gcc/testsuite/g++.dg/coroutines/pr105287.C b/gcc/testsuite/g++.dg/coroutines/pr105287.C\nindex 0436572624d..2db616ce478 100644\n--- a/gcc/testsuite/g++.dg/coroutines/pr105287.C\n+++ b/gcc/testsuite/g++.dg/coroutines/pr105287.C\n@@ -1,4 +1,6 @@\n // { dg-additional-options \"-fanalyzer\" }\n+// { dg-excess-errors \"PR105382\" }\n+// But we should't ICE.\n \n namespace std {\n template <typename _Result> struct coroutine_traits : _Result {};\ndiff --git a/gcc/testsuite/g++.dg/coroutines/pr121643.C b/gcc/testsuite/g++.dg/coroutines/pr121643.C\nnew file mode 100644\nindex 00000000000..e03afdcb35f\n--- /dev/null\n+++ b/gcc/testsuite/g++.dg/coroutines/pr121643.C\n@@ -0,0 +1,29 @@\n+// PR c++/121643\n+\n+#include <coroutine>\n+\n+struct Detached {\n+ struct promise_type {\n+ Detached get_return_object() const noexcept { return {}; }\n+ std::suspend_never initial_suspend() const noexcept { return {}; }\n+ void return_void() const noexcept {}\n+ void unhandled_exception() const noexcept { }\n+ std::suspend_never final_suspend() const noexcept { return {}; }\n+ };\n+};\n+\n+struct Awaiter {\n+ bool await_ready() noexcept { return true; }\n+ void\n+ await_suspend(std::coroutine_handle<> h,\n+ int sloc = 1)\n+ noexcept\n+ {}\n+ void await_resume() noexcept {}\n+};\n+\n+Detached\n+coroutine()\n+{\n+ co_await Awaiter{};\n+}\ndiff --git a/gcc/testsuite/g++.dg/coroutines/pr123975.C b/gcc/testsuite/g++.dg/coroutines/pr123975.C\nnew file mode 100644\nindex 00000000000..c7cad15cf88\n--- /dev/null\n+++ b/gcc/testsuite/g++.dg/coroutines/pr123975.C\n@@ -0,0 +1,52 @@\n+// PR c++/123975\n+// { dg-do run { target c++20 } }\n+#include <coroutine>\n+\n+#if DEBUG\n+#define PRINTF(...) __builtin_printf (__VA_ARGS__)\n+#else\n+#define PRINTF(...)\n+#endif\n+\n+struct task {\n+ bool await_ready() const { return false; }\n+ void await_suspend(auto &&h);\n+ void await_resume() {}\n+\n+ struct promise_type {\n+ task get_return_object() { return task{}; }\n+ void return_void() {}\n+ void unhandled_exception() {}\n+ auto initial_suspend() noexcept { return std::suspend_never{}; }\n+ auto final_suspend() noexcept { return std::suspend_never{}; }\n+\n+ promise_type();\n+ promise_type(const promise_type& p)\n+ { PRINTF (\"%p: promise copied from %p\\n\", this, &p); }\n+ ~promise_type() { PRINTF (\"%p: promise destroyed\\n\", this); }\n+ };\n+};\n+\n+const task::promise_type *first;\n+task::promise_type::promise_type()\n+{\n+ if (!first) first = this;\n+ PRINTF (\"%p: promise constructed\\n\", this);\n+}\n+void task::await_suspend (auto &&h)\n+{\n+ auto &p = h.promise();\n+ PRINTF (\"suspend %p\\n\", &h.promise());\n+ if (&p != first) __builtin_abort ();\n+}\n+\n+task f() { co_return; }\n+\n+task g() {\n+ co_await f();\n+}\n+\n+int main()\n+{\n+ g();\n+}\n", "prefixes": [] }