{"id":2224714,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2224714/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/patch/20260417211459.445911-1-polacek@redhat.com/","project":{"id":17,"url":"http://patchwork.ozlabs.org/api/1.1/projects/17/?format=json","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":"<20260417211459.445911-1-polacek@redhat.com>","date":"2026-04-17T21:14:59","name":"c++/reflection: dependent type considered consteval-only [PR124855]","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"685d53fc17ca1dfa3a7eaa6761123ed81a7fd788","submitter":{"id":14370,"url":"http://patchwork.ozlabs.org/api/1.1/people/14370/?format=json","name":"Marek Polacek","email":"polacek@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/gcc/patch/20260417211459.445911-1-polacek@redhat.com/mbox/","series":[{"id":500404,"url":"http://patchwork.ozlabs.org/api/1.1/series/500404/?format=json","web_url":"http://patchwork.ozlabs.org/project/gcc/list/?series=500404","date":"2026-04-17T21:14:59","name":"c++/reflection: dependent type considered consteval-only [PR124855]","version":1,"mbox":"http://patchwork.ozlabs.org/series/500404/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2224714/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2224714/checks/","tags":{},"headers":{"Return-Path":"","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=QsfP4RIC;\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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a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;\n s=mimecast20190719; t=1776460508;\n h=from:from:reply-to:subject:subject:date:date:message-id:message-id:\n to:to:cc:mime-version:mime-version:content-type:content-type:\n content-transfer-encoding:content-transfer-encoding;\n bh=/Kovd0PjpPRMRKjoAeCW2NdGX8246NSF+oolkWASo0A=;\n b=QsfP4RICLmu0D3jv7GOLLVSGP7eiROqxdqPliI4LeiGLzLF7YS39GMoXQd4VA/VMt25F+p\n 6alML513gzSZiDNTAIea+WYB6P7T00A009LB7p7SXgWZkfv8suExqajVg639ULsYXSEZZY\n y2axriLU9YYTcCpXuwL3wapOM6M3T54=","X-MC-Unique":"X35DaWj8NNKu9rqC_rfCSw-1","X-Mimecast-MFC-AGG-ID":"X35DaWj8NNKu9rqC_rfCSw_1776460505","From":"Marek Polacek ","To":"GCC Patches , Jason Merrill ,\n Jakub Jelinek ","Subject":"[PATCH] c++/reflection: dependent type considered consteval-only\n [PR124855]","Date":"Fri, 17 Apr 2026 17:14:59 -0400","Message-ID":"<20260417211459.445911-1-polacek@redhat.com>","MIME-Version":"1.0","X-Scanned-By":"MIMEDefang 3.4.1 on 10.30.177.111","X-Mimecast-Spam-Score":"0","X-Mimecast-MFC-PROC-ID":"1q1HCOxVATBlREr5JCUCmeKMkp_i_MAkebrZ9DBOV44_1776460505","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 ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org"},"content":"Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?\n\n-- >8 --\nHere we emit the \"function of consteval-only type must be declared\n'consteval'\" error for f, even though its type will become\nchar f(int) after substitution, which is not consteval-only. We\nprobably shouldn't consider dependent type consteval-only.\n\n\tPR c++/124855\n\ngcc/cp/ChangeLog:\n\n\t* reflect.cc (consteval_only_p): Return false if the type is\n\tdependent.\n\ngcc/testsuite/ChangeLog:\n\n\t* g++.dg/reflect/type11.C: New test.\n---\n gcc/cp/reflect.cc | 4 ++++\n gcc/testsuite/g++.dg/reflect/type11.C | 10 ++++++++++\n 2 files changed, 14 insertions(+)\n create mode 100644 gcc/testsuite/g++.dg/reflect/type11.C\n\n\nbase-commit: dd723b26663c76440ae44e83f0c699240c75b81e","diff":"diff --git a/gcc/cp/reflect.cc b/gcc/cp/reflect.cc\nindex 97b6e76c652..167123b3f2d 100644\n--- a/gcc/cp/reflect.cc\n+++ b/gcc/cp/reflect.cc\n@@ -8630,6 +8630,10 @@ consteval_only_p (tree t)\n which could be consteval-only, depending on T. */\n t = complete_type (t);\n \n+ /* For dependent types we can't be sure if this type is consteval-only. */\n+ if (dependent_type_p (t))\n+ return false;\n+\n /* Classes with std::meta::info members are also consteval-only. */\n hash_set visited;\n return !!cp_walk_tree (&t, consteval_only_type_r, &visited, &visited);\ndiff --git a/gcc/testsuite/g++.dg/reflect/type11.C b/gcc/testsuite/g++.dg/reflect/type11.C\nnew file mode 100644\nindex 00000000000..11024ff4606\n--- /dev/null\n+++ b/gcc/testsuite/g++.dg/reflect/type11.C\n@@ -0,0 +1,10 @@\n+// PR c++/124855\n+// { dg-do compile { target c++26 } }\n+// { dg-additional-options \"-freflection\" }\n+\n+using mi = decltype(^^::);\n+\n+template\n+auto f(T) -> [: ^^T == ^^int ? ^^char : mi{} :];\n+\n+static_assert(sizeof(f(0)) == 1);\n","prefixes":[]}