c++: Reject array new with -fexceptions with deleted dtor [PR123030]

c++: Reject array new with -fexceptions with deleted dtor [PR123030]

For array new and -fexceptions, we only try to build cleanup if
TYPE_HAS_NONTRIVIAL_DESTRUCTOR and so don't complain if the
array element has trivial but deleted destructor.

The following patch changes it to build the dtor whenever
type_build_dtor_call but only registers it as cleanup if the cleanup
has TREE_SIDE_EFFECTS.  build_vec_delete_1 has a special
case for these type_build_dtor_call && !TYPE_HAS_NONTRIVIAL_DESTRUCTOR
cases where it does less work.

Though, I wonder if we also shouldn't test whether the ctor isn't noexcept,
then we wouldn't have to change the new4.C test.  Though, clang++ rejects
that as well even when it has noexcept ctor.

2025-12-19  Jakub Jelinek  <jakub@redhat.com>

	PR c++/123030
	* init.cc (build_vec_init): Call build_vec_delete_1 for -fexceptions
	even if just type_build_dtor_call, not only when
	TYPE_HAS_NONTRIVIAL_DESTRUCTOR.  But register cleanups only
	for TYPE_HAS_NONTRIVIAL_DESTRUCTOR.

	* g++.dg/cpp0x/deleted18.C: New test.
	* g++.dg/cpp0x/new4.C: Expect an error.