On 9/23/24 4:44 AM, Simon Martin wrote:
Hi Jason,
On 20 Sep 2024, at 18:01, Jason Merrill wrote:
On 9/20/24 5:21 PM, Simon Martin wrote:
The following code triggers an ICE
=== cut here ===
class base {};
class derived : virtual public base {
public:
template<typename Arg> constexpr derived(Arg) {}
};
int main() {
derived obj(1.);
}
=== cut here ===
The problem is that cxx_bind_parameters_in_call ends up attempting to
convert a REAL_CST (the first non artificial parameter) to
INTEGER_TYPE
(the type of the __in_chrg parameter), which ICEs.
This patch teaches cxx_bind_parameters_in_call to handle the
__in_chrg
and __vtt_parm parameters that {con,de}structors might have.
Note that in the test case, the constructor is not
constexpr-suitable,
however it's OK since it's a template according to my read of
paragraph
(3) of [dcl.constexpr].
Agreed.
It looks like your patch doesn't correct the mismatching of arguments
to parameters that you describe, but at least for now it should be
enough to set *non_constant_p and return if we see a VTT or in-charge
parameter.
Thanks, it’s true that my initial patch was wrong in that we’d leave
cxx_bind_parameters_in_call thinking the expression was actually a
constant expression :-/
The attached revised patch follows your suggestion (thanks!).
Successfully tested on x86_64-pc-linux-gnu. OK for trunk?
After this patch I'm seeing a regression on constexpr-dynamic10.C with
-fimplicit-constexpr; we also need to give an error here when
(!ctx->quiet).
Jason
