From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 89FFF3858D3C; Sun, 16 Jul 2023 00:46:00 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 89FFF3858D3C
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1689468360;
	bh=kyY72izIFP+rirerMJbya4XhuVm5J5Mn8vIfZKF8nxQ=;
	h=From:To:Subject:Date:From;
	b=Eaz3ZV+/nUui/WsCzgt/vdr4NADKKLlt3LXw1I3hotMhbsnTY0bFJt0CEuAuEVgma
	 hXbWn3PvSYL9vOQmNO4acXcVn+MJB6BToSB0J77Gvlbo+jCHfZLoMnxTAzFrITB2dG
	 WQ0vn0+q/QGxsv8XbaQtQuNaC8UgyuMpugZa7hU0=
From: "eric.niebler at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/110680] New: erroneous error "non-template type 'C' used as
 a template"
Date: Sun, 16 Jul 2023 00:46:00 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: c++
X-Bugzilla-Version: 14.0
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: eric.niebler at gmail dot com
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status
 bug_severity priority component assigned_to reporter target_milestone
Message-ID: <bug-110680-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110680

            Bug ID: 110680
           Summary: erroneous error "non-template type 'C' used as a
                    template"
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: eric.niebler at gmail dot com
  Target Milestone: ---

The following valid C++20 is rejected by gcc trunk:


  template <auto X =3D []{}>
  struct S {
    auto f() { return X; }
  };

  template <class T>
  using C =3D decltype(S().f());

  using D =3D C<int>;


<source>:29:16: error: non-template type 'C' used as a template
   29 | using D =3D C<int>;
      |                ^
Compiler returned: 1


https://godbolt.org/z/b3eY8fWTv=