public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug c++/106604] New: Fully-specified deduction guide in anonymous namespace warns as-if a function? Unsuppressably?
@ 2022-08-13 0:17 nabijaczleweli at nabijaczleweli dot xyz
2022-08-14 19:36 ` [Bug c++/106604] " pinskia at gcc dot gnu.org
` (3 more replies)
0 siblings, 4 replies; 5+ messages in thread
From: nabijaczleweli at nabijaczleweli dot xyz @ 2022-08-13 0:17 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106604
Bug ID: 106604
Summary: Fully-specified deduction guide in anonymous namespace
warns as-if a function? Unsuppressably?
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: nabijaczleweli at nabijaczleweli dot xyz
Target Milestone: ---
Reproduced this separately on 10.2.1-6 (bullseye), 12.1.0-7 (sid from 2 weeks
ago), trunk (according to godbolt).
TL;DR: https://gcc.godbolt.org/z/869TdbvEe
Given:
namespace {
template <class T>
struct test {
test(T) noexcept {}
};
UNUSED test(bool) -> test<bool>;
}
If UNUSED is blank, GCC produces:
<source>:7:12: warning: '{anonymous}::test(int) -> test<int>' declared
'static' but never defined [-Wunused-function]
7 | UNUSED test(int) -> test<int>;
| ^~~~
Compiler returned: 0
If UNUSED is [[maybe_unused]] (which was my solution originally since it works
on Clang):
<source>:0:16: error: 'decl-specifier' in declaration of deduction guide
0 | #define UNUSED [[maybe_unused]]
| ^
<source>:7:5: note: in expansion of macro 'UNUSED'
7 | UNUSED test(int) -> test<int>;
| ^~~~~~
<source>:7:12: warning: '{anonymous}::test(int) -> test<int>' declared
'static' but never defined [-Wunused-function]
7 | UNUSED test(int) -> test<int>;
| ^~~~
Compiler returned: 1
So:
* the deduction guide is decidedly not "declared 'static'" (anon namespace
means it has static linkage, sure, but it's not 'static')
* of course it's not defined?? can you even define a deduction guide?
* how do you suppress this? (besides template<class = void>)?
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/106604] Fully-specified deduction guide in anonymous namespace warns as-if a function? Unsuppressably?
2022-08-13 0:17 [Bug c++/106604] New: Fully-specified deduction guide in anonymous namespace warns as-if a function? Unsuppressably? nabijaczleweli at nabijaczleweli dot xyz
@ 2022-08-14 19:36 ` pinskia at gcc dot gnu.org
2023-05-19 4:19 ` pinskia at gcc dot gnu.org
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: pinskia at gcc dot gnu.org @ 2022-08-14 19:36 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106604
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Last reconfirmed| |2022-08-14
Status|UNCONFIRMED |NEW
Known to fail| |7.1.0
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/106604] Fully-specified deduction guide in anonymous namespace warns as-if a function? Unsuppressably?
2022-08-13 0:17 [Bug c++/106604] New: Fully-specified deduction guide in anonymous namespace warns as-if a function? Unsuppressably? nabijaczleweli at nabijaczleweli dot xyz
2022-08-14 19:36 ` [Bug c++/106604] " pinskia at gcc dot gnu.org
@ 2023-05-19 4:19 ` pinskia at gcc dot gnu.org
2023-08-12 1:13 ` cvs-commit at gcc dot gnu.org
2023-08-15 13:19 ` ppalka at gcc dot gnu.org
3 siblings, 0 replies; 5+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-05-19 4:19 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106604
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |development at jordi dot vilar.cat
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 107587 has been marked as a duplicate of this bug. ***
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/106604] Fully-specified deduction guide in anonymous namespace warns as-if a function? Unsuppressably?
2022-08-13 0:17 [Bug c++/106604] New: Fully-specified deduction guide in anonymous namespace warns as-if a function? Unsuppressably? nabijaczleweli at nabijaczleweli dot xyz
2022-08-14 19:36 ` [Bug c++/106604] " pinskia at gcc dot gnu.org
2023-05-19 4:19 ` pinskia at gcc dot gnu.org
@ 2023-08-12 1:13 ` cvs-commit at gcc dot gnu.org
2023-08-15 13:19 ` ppalka at gcc dot gnu.org
3 siblings, 0 replies; 5+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2023-08-12 1:13 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106604
--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Patrick Palka <ppalka@gcc.gnu.org>:
https://gcc.gnu.org/g:f50f603cbfd05653555e9856360c83108bbd1d8a
commit r14-3175-gf50f603cbfd05653555e9856360c83108bbd1d8a
Author: Patrick Palka <ppalka@redhat.com>
Date: Fri Aug 11 21:13:23 2023 -0400
c++: bogus warning w/ deduction guide in anon ns [PR106604]
Here we're unintentionally issuing a "declared static but never defined"
warning from wrapup_namespace_globals for a deduction guide declared in
an anonymous namespace. This patch fixes this by giving deduction guides
a dummy DECL_INITIAL, which suppresses the warning and also allows us to
simplify redeclaration checking for them.
Co-authored-by: Jason Merrill <jason@redhat.com>
PR c++/106604
gcc/cp/ChangeLog:
* decl.cc (redeclaration_error_message): Remove special handling
for deduction guides.
(grokfndecl): Give deduction guides a dummy DECL_INITIAL.
gcc/testsuite/ChangeLog:
* g++.dg/cpp1z/class-deduction74.C: Expect "defined" instead
of "declared" in the repeated deduction guide diagnostics.
* g++.dg/cpp1z/class-deduction116.C: New test.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/106604] Fully-specified deduction guide in anonymous namespace warns as-if a function? Unsuppressably?
2022-08-13 0:17 [Bug c++/106604] New: Fully-specified deduction guide in anonymous namespace warns as-if a function? Unsuppressably? nabijaczleweli at nabijaczleweli dot xyz
` (2 preceding siblings ...)
2023-08-12 1:13 ` cvs-commit at gcc dot gnu.org
@ 2023-08-15 13:19 ` ppalka at gcc dot gnu.org
3 siblings, 0 replies; 5+ messages in thread
From: ppalka at gcc dot gnu.org @ 2023-08-15 13:19 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106604
Patrick Palka <ppalka at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |ppalka at gcc dot gnu.org
Target Milestone|--- |14.0
Resolution|--- |FIXED
Status|NEW |RESOLVED
--- Comment #4 from Patrick Palka <ppalka at gcc dot gnu.org> ---
Fixed for GCC 14.
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2023-08-15 13:19 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-08-13 0:17 [Bug c++/106604] New: Fully-specified deduction guide in anonymous namespace warns as-if a function? Unsuppressably? nabijaczleweli at nabijaczleweli dot xyz
2022-08-14 19:36 ` [Bug c++/106604] " pinskia at gcc dot gnu.org
2023-05-19 4:19 ` pinskia at gcc dot gnu.org
2023-08-12 1:13 ` cvs-commit at gcc dot gnu.org
2023-08-15 13:19 ` ppalka at gcc dot gnu.org
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).