Dredd mutate constexpr inside if-condition

[JonathanFoo0523]

When dredd is applied to the following file:

template <int a> void foo() {
  if constexpr (a) {};
}

int main() {
  foo<0>;
}

The constexpr is mutated:

template <int a> void foo() {
  if (!__dredd_enabled_mutation(3)) { if constexpr (__dredd_replace_expr_bool(a, 0)) {}; }
}

int main() {
  foo<0>;
}

This results in compilation error:

constexpr if condition is not a constant expression

I can't replicate the problem without the use of template.