public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
* [Bug c++/101588] New: rejects valid constexpr when binding from a constexpr function
@ 2021-07-23 2:17 pinskia at gcc dot gnu.org
2021-07-23 2:22 ` [Bug c++/101588] rejects valid constexpr when binding from a constexpr function and initializer_list pinskia at gcc dot gnu.org
` (3 more replies)
0 siblings, 4 replies; 5+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-07-23 2:17 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101588
Bug ID: 101588
Summary: rejects valid constexpr when binding from a constexpr
function
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Keywords: rejects-valid
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: pinskia at gcc dot gnu.org
Target Milestone: ---
Split out from PR 66287.
Take:
struct T { int i; };
constexpr T copy(const T& v) { return v; }
constexpr const auto& r = T{42};
constexpr const auto& c = copy(r);
int main() {}
----- CUT ----
This should be accepted by GCC but currently is rejected:
<source>:11:33: error: modification of '<temporary>' is not a constant
expression
11 | constexpr const auto& c = copy(r);
| ^
^ permalink raw reply [flat|nested] 5+ messages in thread* [Bug c++/101588] rejects valid constexpr when binding from a constexpr function and initializer_list 2021-07-23 2:17 [Bug c++/101588] New: rejects valid constexpr when binding from a constexpr function pinskia at gcc dot gnu.org @ 2021-07-23 2:22 ` pinskia at gcc dot gnu.org 2021-07-23 2:34 ` [Bug c++/101588] [DR2126] " pinskia at gcc dot gnu.org ` (2 subsequent siblings) 3 siblings, 0 replies; 5+ messages in thread From: pinskia at gcc dot gnu.org @ 2021-07-23 2:22 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101588 --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Note clang was only fixed in clang 12. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/101588] [DR2126] rejects valid constexpr when binding from a constexpr function and initializer_list 2021-07-23 2:17 [Bug c++/101588] New: rejects valid constexpr when binding from a constexpr function pinskia at gcc dot gnu.org 2021-07-23 2:22 ` [Bug c++/101588] rejects valid constexpr when binding from a constexpr function and initializer_list pinskia at gcc dot gnu.org @ 2021-07-23 2:34 ` pinskia at gcc dot gnu.org 2023-02-09 0:23 ` mpolacek at gcc dot gnu.org 2023-02-10 0:07 ` mpolacek at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: pinskia at gcc dot gnu.org @ 2021-07-23 2:34 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101588 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Summary|rejects valid constexpr |[DR2126] rejects valid |when binding from a |constexpr when binding from |constexpr function and |a constexpr function and |initializer_list |initializer_list Alias| |DR2126 --- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- GCC implements DR2126 mostly except when the type is intialized like: T{42} . ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/101588] [DR2126] rejects valid constexpr when binding from a constexpr function and initializer_list 2021-07-23 2:17 [Bug c++/101588] New: rejects valid constexpr when binding from a constexpr function pinskia at gcc dot gnu.org 2021-07-23 2:22 ` [Bug c++/101588] rejects valid constexpr when binding from a constexpr function and initializer_list pinskia at gcc dot gnu.org 2021-07-23 2:34 ` [Bug c++/101588] [DR2126] " pinskia at gcc dot gnu.org @ 2023-02-09 0:23 ` mpolacek at gcc dot gnu.org 2023-02-10 0:07 ` mpolacek at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: mpolacek at gcc dot gnu.org @ 2023-02-09 0:23 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101588 Marek Polacek <mpolacek at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Ever confirmed|0 |1 Last reconfirmed| |2023-02-09 CC| |mpolacek at gcc dot gnu.org Status|UNCONFIRMED |NEW --- Comment #3 from Marek Polacek <mpolacek at gcc dot gnu.org> --- This came up again in bug 107079. The static_assert should pass after fixing bug 107079 but doesn't because we don't fully implement the -- a temporary object of non-volatile const-qualified literal type whose lifetime is extended ([class.temporary]) to that of a variable that is usable in constant expressions, or bullet. struct X { const X* x = this; }; constexpr const X& x = X{}; static_assert(x.x == &x); ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c++/101588] [DR2126] rejects valid constexpr when binding from a constexpr function and initializer_list 2021-07-23 2:17 [Bug c++/101588] New: rejects valid constexpr when binding from a constexpr function pinskia at gcc dot gnu.org ` (2 preceding siblings ...) 2023-02-09 0:23 ` mpolacek at gcc dot gnu.org @ 2023-02-10 0:07 ` mpolacek at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: mpolacek at gcc dot gnu.org @ 2023-02-10 0:07 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101588 --- Comment #4 from Marek Polacek <mpolacek at gcc dot gnu.org> --- When fixing this, please adjust g++.dg/cpp0x/constexpr-nsdmi2.C. ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2023-02-10 0:07 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-07-23 2:17 [Bug c++/101588] New: rejects valid constexpr when binding from a constexpr function pinskia at gcc dot gnu.org 2021-07-23 2:22 ` [Bug c++/101588] rejects valid constexpr when binding from a constexpr function and initializer_list pinskia at gcc dot gnu.org 2021-07-23 2:34 ` [Bug c++/101588] [DR2126] " pinskia at gcc dot gnu.org 2023-02-09 0:23 ` mpolacek at gcc dot gnu.org 2023-02-10 0:07 ` mpolacek 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).