PR c++/89036 reports an ICE due to this assertion failing
1136 /* A class should never have more than one destructor. */
1137 gcc_assert (!current_fns || via_using || !DECL_DESTRUCTOR_P (method));
on this template with a pair of dtors, with
mutually exclusive "requires" clauses:
template<typename T>
struct Y {
~Y() requires(true) = default;
~Y() requires(false) {}
};
(is this valid? my knowledge of this part of C++ is fairly hazy)
Nathan introduced this assertion as part of:
ca9219bf18c68a001d62ecb981bc9176b0feaf12 (aka r251340):
2017-08-24 Nathan Sidwell <nat...@acm.org>
Conversion operators kept on single overload set
which, amongst other changes to add_method had this:
/* A class should never have more than one destructor. */
- if (current_fns && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method))
- return false;
+ gcc_assert (!current_fns || !DECL_DESTRUCTOR_P (method));
The following patch generalizes the assertion to allow for multiple
dtors if they have "requires" clauses. (I already generalized
the assertion in another way in r268041 to fix PR c++/88699;
alternatively, is this too much like whack-a-mole, and would
dropping the assertion altogether be better?)
Successfully bootstrapped & regrtested on x86_64-pc-linux-gnu.
OK for trunk?
gcc/cp/ChangeLog:
PR c++/89036
* class.c (add_method): Generalize assertion to allow for
multiple dtors if they have "requires" clauses.
gcc/testsuite/ChangeLog:
PR c++/89036
* g++.dg/concepts/pr89036.C: New test.
---
gcc/cp/class.c | 11 +++++++++--
gcc/testsuite/g++.dg/concepts/pr89036.C | 8 ++++++++
2 files changed, 17 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/concepts/pr89036.C
diff --git a/gcc/cp/class.c b/gcc/cp/class.c
index e8773c2..fb46f92 100644
--- a/gcc/cp/class.c
+++ b/gcc/cp/class.c
@@ -1133,8 +1133,15 @@ add_method (tree type, tree method, bool via_using)
}
}
- /* A class should never have more than one destructor. */
- gcc_assert (!current_fns || via_using || !DECL_DESTRUCTOR_P (method));
+ /* A class should never have more than one destructor... */
+ gcc_assert (!current_fns
+ || via_using
+ || !DECL_DESTRUCTOR_P (method)
+ /* ...unless the destructors are constrained by "requires"
+ clauses. */
+ || (flag_concepts
+ && get_constraints (method)
+ && CI_DECLARATOR_REQS (get_constraints (method))));
current_fns = ovl_insert (method, current_fns, via_using);
diff --git a/gcc/testsuite/g++.dg/concepts/pr89036.C
b/gcc/testsuite/g++.dg/concepts/pr89036.C
new file mode 100644
index 0000000..f83ef8b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/concepts/pr89036.C
@@ -0,0 +1,8 @@
+// { dg-do compile { target c++11 } }
+// { dg-options "-fconcepts" }
+
+template<typename T>
+struct Y {
+ ~Y() requires(true) = default;
+ ~Y() requires(false) {}
+};
--
1.8.5.3
