[Bug c++/92505] Using mutable in constexpr
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92505 Patrick Palka changed: What|Removed |Added Target Milestone|--- |13.0 Status|ASSIGNED|RESOLVED Resolution|--- |FIXED --- Comment #6 from Patrick Palka --- Fixed for GCC 13.
[Bug c++/92505] Using mutable in constexpr
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92505 --- Comment #5 from CVS Commits --- The master branch has been updated by Patrick Palka : https://gcc.gnu.org/g:7107ea6fb933f1e928593c7e92edfd64ccf0df63 commit r13-2701-g7107ea6fb933f1e928593c7e92edfd64ccf0df63 Author: Patrick Palka Date: Fri Sep 16 11:10:43 2022 -0400 c++: 'mutable' member within constexpr [PR92505] This patch permits accessing 'mutable' members of local objects during constexpr evaluation, while continuing to reject it for global objects (as in the last line of cpp0x/constexpr-mutable1.C). To distinguish between the two cases, it looks like it suffices to just check CONSTRUCTOR_MUTABLE_POSION in cxx_eval_component_reference before deciding to reject a DECL_MUTABLE_P member access. PR c++/92505 gcc/cp/ChangeLog: * constexpr.cc (cxx_eval_component_reference): Check non_constant_p sooner. In C++14 or later, reject a DECL_MUTABLE_P member access only if CONSTRUCTOR_MUTABLE_POISION is also set. gcc/testsuite/ChangeLog: * g++.dg/cpp0x/constexpr-mutable3.C: New test. * g++.dg/cpp1y/constexpr-mutable1.C: New test.
[Bug c++/92505] Using mutable in constexpr
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92505 Patrick Palka changed: What|Removed |Added CC||ppalka at gcc dot gnu.org Status|NEW |ASSIGNED Assignee|unassigned at gcc dot gnu.org |ppalka at gcc dot gnu.org
[Bug c++/92505] Using mutable in constexpr
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92505
Arthur O'Dwyer changed:
What|Removed |Added
CC||arthur.j.odwyer at gmail dot
com
--- Comment #4 from Arthur O'Dwyer ---
Confirmed; the test case can be as simple as
// https://godbolt.org/z/M9rf31qqq
struct S { mutable int m; };
static_assert(S{42}.m == 42);
(Removing the "mutable" keyword makes GCC happy.)
[Bug c++/92505] Using mutable in constexpr
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92505 Christopher Di Bella changed: What|Removed |Added CC||cjdb.ns at gmail dot com --- Comment #3 from Christopher Di Bella --- Gentle ping, this has started to cause issues in the libc++ GCC CI for ranges.
[Bug c++/92505] Using mutable in constexpr
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92505
--- Comment #2 from Marek Polacek ---
cxx_eval_component_reference has:
2967 if (DECL_MUTABLE_P (part))
2968 {
2969 if (!ctx->quiet)
2970 error ("mutable %qD is not usable in a constant expression",
part);
2971 *non_constant_p = true;
2972 }
Added in https://gcc.gnu.org/ml/gcc-patches/2011-10/msg02593.html
I will need to do a bit of archeology on the isocpp mailing list to see the
discussions.
[Bug c++/92505] Using mutable in constexpr
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92505 Marek Polacek changed: What|Removed |Added Status|UNCONFIRMED |NEW Last reconfirmed||2019-11-14 CC||mpolacek at gcc dot gnu.org Ever confirmed|0 |1 --- Comment #1 from Marek Polacek --- Looks like this never worked.
