From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id D1230385840F; Thu, 9 Mar 2023 19:33:44 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org D1230385840F DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1678390424; bh=nUHH8SPdCLR2oxZcoVY7u4d6AjfN89y6lK/W43eSWZ4=; h=From:To:Subject:Date:From; b=nSulCAvimQsZKPglOnksnC1jhTMkE1X1qXzFM6PQsHiFpJH1loYCj2/tXtZcVG630 iQT0FUpGTlm+fV16er0CN9gxxUPUxIHc73X3wmcAFGpYoqw8JdykA2QBYMu3UwxqWT ZP3yOwT2lpCmAjajN7Nei8e0cb786R/K7iN0N2UI= From: "brignon.enzo at protonmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/109084] New: requires keyword can't access private static constexpr bool in templated class Date: Thu, 09 Mar 2023 19:33:44 +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: 12.2.1 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: brignon.enzo at protonmail 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 attachments.created Message-ID: 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: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109084 Bug ID: 109084 Summary: requires keyword can't access private static constexpr bool in templated class Product: gcc Version: 12.2.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: brignon.enzo at protonmail dot com Target Milestone: --- Created attachment 54626 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=3D54626&action=3Dedit The minimal reproduction file (not preprocessed because it does not include anything) When using requires keyword to enable class member function using a private static constexpr bool (eventually the value of a concept) in a templated cl= ass gcc fails to access the given boolean variable because it is private within= its context.=20 It does not fail if the boolean is public or if the class is not templated. You can find a minimal example (not preprocessed because it needs no includ= e) in attachment. Output of gcc -v: Using built-in specs. COLLECT_GCC=3Dgcc COLLECT_LTO_WRAPPER=3D/usr/lib/gcc/x86_64-pc-linux-gnu/12.2.1/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: /build/gcc/src/gcc/configure --enable-languages=3Dc,c++,ada,fortran,go,lto,objc,obj-c++,d --enable-boots= trap --prefix=3D/usr --libdir=3D/usr/lib --libexecdir=3D/usr/lib --mandir=3D/usr= /share/man --infodir=3D/usr/share/info --with-bugurl=3Dhttps://bugs.archlinux.org/ --with-build-config=3Dbootstrap-lto --with-linker-hash-style=3Dgnu --with-system-zlib --enable-__cxa_atexit --enable-cet=3Dauto --enable-checking=3Drelease --enable-clocale=3Dgnu --enable-default-pie --enable-default-ssp --enable-gnu-indirect-function --enable-gnu-unique-obj= ect --enable-libstdcxx-backtrace --enable-link-serialization=3D1 --enable-linker-build-id --enable-lto --enable-multilib --enable-plugin --enable-shared --enable-threads=3Dposix --disable-libssp --disable-libstdc= xx-pch --disable-werror Thread model: posix Supported LTO compression algorithms: zlib zstd gcc version 12.2.1 20230201 (GCC)=20 The file is complied with following options: g++ -std=3Dc++20 bug.cpp Output of gcc: bug.cpp: In function 'int main()': bug.cpp:12:15: error: class template argument deduction failed: 12 | MyClass c{}; | ^ bug.cpp:12:15: error: no matching function for call to 'MyClass()' bug.cpp:8:5: note: candidate: 'template requires=20 MyClass::cond MyClass()-> MyClass' 8 | MyClass() {} | ^~~~~~~ bug.cpp:8:5: note: template argument deduction/substitution failed: bug.cpp:8:5: note: constraints not satisfied bug.cpp: In substitution of 'template requires=20 MyClass::cond MyClass()-> MyClass [with T =3D int; Enable =3D void]': bug.cpp:12:15: required from here bug.cpp:8:5: required by the constraints of 'template=20 requires MyClass::cond MyClass()-> MyClass' bug.cpp:12:15: error: 'constexpr const bool MyClass::cond' is private within this context 12 | MyClass c{}; | ^ bug.cpp:5:27: note: declared private here 5 | static constexpr bool cond =3D true; | ^~~~ bug.cpp:3:7: note: candidate: 'template MyClass(MyClass)-> MyClass' 3 | class MyClass { | ^~~~~~~ bug.cpp:3:7: note: template argument deduction/substitution failed: bug.cpp:12:15: note: candidate expects 1 argument, 0 provided 12 | MyClass c{}; |=