c++: Fix bogus error with __integer_pack [PR94490]

Here we issue a bogus:

error: '(0 ? fake_tuple_size_v<int> : fake_tuple_size_v<int>)' is not a constant expression

because cxx_constant_value in expand_integer_pack gets

*(0 ? VIEW_CONVERT_EXPR<const int>(fake_tuple_size_v) : VIEW_CONVERT_EXPR<const int>(fake_tuple_size_v))

which is a REFERENCE_REF_P and we evaluate its operand to 3, so we end
up with *3 and that fails.  Sounds like we need to get rid of the
REFERENCE_REF_P then.  That is what tsubst_copy_and_build/INDIRECT_REF
will do:

        if (REFERENCE_REF_P (t))
          {
            /* A type conversion to reference type will be enclosed in
               such an indirect ref, but the substitution of the cast
               will have also added such an indirect ref.  */
            r = convert_from_reference (r);
          }

so I think it's reasonable to call instantiate_non_dependent_expr_sfinae.

	PR c++/94490

gcc/cp/ChangeLog:

	* pt.c (expand_integer_pack): Call
	instantiate_non_dependent_expr_sfinae.

gcc/testsuite/ChangeLog:

	* g++.dg/ext/integer-pack5.C: New test.

0 files changed, 0 insertions, 0 deletions