public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/106211] Rejects valid with function template with non-deduced parameters from deduced parameters of another function template
Date: Wed, 06 Jul 2022 22:34:24 +0000 [thread overview]
Message-ID: <bug-106211-4-THUyAXKkCJ@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-106211-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106211
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The question comes about variadic templates and deduction of auto.
>Further, all three compilers also accept this minor modification:
This one does need any deduction though so it is not even related.
So let's take the slightly reduced testcase:
template<typename, typename>
concept any = true;
auto t = []<typename... Ts>(Ts...) {
return [](any<Ts> auto... b, auto c) {return c;};
}(1);
auto t1 = t(2, 3);
We have now:
Ts being <int>
so we get:
return [](any<int> auto, auto) {};
Which is invalid as any<int> is invalid.
Maybe I misunderstand how this works though.
If we remove the any<Ts> then we get the same failure for clang as GCC:
<source>:7:11: error: no matching function for call to object of type '(lambda
at <source>:5:12)'
auto t1 = t(2, 3);
^
<source>:5:12: note: candidate function [with b:auto = <>, c:auto = int] not
viable: requires single argument 'c', but 2 arguments were provided
return [](auto... b, auto c) {return c;};
^
Which is to say the problem is the way variadic templates with auto is being
handled. I suspect the concept is being handled incorrectly for clang.
next prev parent reply other threads:[~2022-07-06 22:34 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-06 3:31 [Bug c++/106211] New: " davidfromonline at gmail dot com
2022-07-06 20:59 ` [Bug c++/106211] " pinskia at gcc dot gnu.org
2022-07-06 22:22 ` davidfromonline at gmail dot com
2022-07-06 22:34 ` pinskia at gcc dot gnu.org [this message]
2022-07-06 22:39 ` davidfromonline at gmail dot com
2024-04-11 23:48 ` pinskia at gcc dot gnu.org
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=bug-106211-4-THUyAXKkCJ@http.gcc.gnu.org/bugzilla/ \
--to=gcc-bugzilla@gcc.gnu.org \
--cc=gcc-bugs@gcc.gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).