[Bug c++/96840] [11 Regression] Recursive substitution in constrained commutative operator
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96840 --- Comment #5 from Johel Ernesto Guerrero Peña --- I think I was wrong and this has not regressed.
[Bug c++/96840] [11 Regression] Recursive substitution in constrained commutative operator
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96840 --- Comment #4 from Johel Ernesto Guerrero Peña --- Seems like this regressed. Do I open a new bug report?
[Bug c++/96840] [11 Regression] Recursive substitution in constrained commutative operator
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96840
Patrick Palka changed:
What|Removed |Added
Resolution|--- |FIXED
Status|WAITING |RESOLVED
--- Comment #3 from Patrick Palka ---
With the above patch we now detect and diagnose the self-recursive satisfaction
in the testcase:
96840.C: In substitution of ‘template requires C void
operator*(T, Int) [with T = int]’:
96840.C:1:64: required by substitution of ‘template requires C void operator*(Int, T) [with T = int]’
96840.C:6:28: required from here
96840.C:1:37: required for the satisfaction of ‘C’ [with T =
Int; Rep = int]
96840.C:1:41: in requirements with ‘T t’, ‘U u’ [with U = int; T = Int]
96840.C:1:41: error: satisfaction of atomic constraint ‘requires(T t, U u) {t *
u;} [with U = Rep; T = T]’ depends on itself
1 | template concept C = requires(T t, U u) { t * u; };
| ^
So I suppose we can mark this PR as resolved.
[Bug c++/96840] [11 Regression] Recursive substitution in constrained commutative operator
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96840 --- Comment #2 from CVS Commits --- The master branch has been updated by Patrick Palka : https://gcc.gnu.org/g:79f57d5cb070bb02ea0a34b5f42658d6659b19a8 commit r11-6245-g79f57d5cb070bb02ea0a34b5f42658d6659b19a8 Author: Patrick Palka Date: Thu Dec 17 22:18:07 2020 -0500 c++: Diagnose self-recursive satisfaction This patch further extends the satisfaction_cache class to diagnose self-recursive satisfaction. gcc/cp/ChangeLog: * constraint.cc (sat_entry::evaluating): New member. (satisfaction_cache::get): If entry->evaluating, diagnose self-recursive satisfaction. Otherwise, set entry->evaluating if we're not reusing a cached satisfaction result. (satisfaction_cache::save): Clear entry->evaluating. (satisfy_atom): Set up diagnosing_failed_constraint before the first call to get(). gcc/testsuite/ChangeLog: PR c++/96840 * g++.dg/cpp2a/concepts-pr88395.C: Adjust to expect the self-recursive satisfaction to get directly diagnosed. * g++.dg/cpp2a/concepts-recursive-sat2.C: Likewise. * g++.dg/cpp2a/concepts-recursive-sat4.C: New test.
[Bug c++/96840] [11 Regression] Recursive substitution in constrained commutative operator
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96840 Richard Biener changed: What|Removed |Added Status|UNCONFIRMED |WAITING Ever confirmed|0 |1 Last reconfirmed||2020-10-16
[Bug c++/96840] [11 Regression] Recursive substitution in constrained commutative operator
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96840 Patrick Palka changed: What|Removed |Added CC||jason at gcc dot gnu.org, ||ppalka at gcc dot gnu.org --- Comment #1 from Patrick Palka --- Started with r11-2774: c++: Check satisfaction before non-dep convs. [CWG2369] It's very hard to use concepts to protect a template from hard errors due to unwanted instantiation if constraints aren't checked until after doing all substitution and checking of non-dependent conversions. We fall into a loop when checking the constraints of the second overload (instantiated with Rep=int and T=Int). It looks like we're correct to reject the testcase as of this DR?
[Bug c++/96840] [11 Regression] Recursive substitution in constrained commutative operator
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96840 Richard Biener changed: What|Removed |Added Keywords||rejects-valid Target Milestone|--- |11.0 Summary|Recursive substitution in |[11 Regression] Recursive |constrained commutative |substitution in constrained |operator|commutative operator
