Here during satisfaction of B's constraints we're failing to reject the
object-less call to the non-static member function A::size ultimately
because satisfaction is performed in the (access) context of the class
template B, which has a dependent base, and so the any_dependent_bases_p
check within build_new_method_call causes us to not reject the call.
(Subsequent constexpr evaluation of the call succeeds since the function
is effectively static.)
This patch fixes this by refining the any_dependent_bases_p check within
build_new_method_call: if we're in a context where 'this' is unavailable,
then we cannot resolve the implicit object regardless of the presence of
a dependent base. So let's also check current_class_ptr alongside a_d_b_p.
PR c++/103831
gcc/cp/ChangeLog:
* call.c (build_new_method_call): Consider dependent bases only
if 'this' is available.
gcc/testsuite/ChangeLog:
* g++.dg/cpp2a/concepts-class3.C: New test.
* g++.dg/template/non-dependent18.C: New test.
we know we really need it. */
cand->first_arg = instance;
}
- else if (any_dependent_bases_p ())
+ else if (current_class_ptr && any_dependent_bases_p ())
/* We can't tell until instantiation time whether we can use
*this as the implicit object argument. */;
else
--- /dev/null
+// PR c++/103831
+// { dg-do compile { target c++20 } }
+
+struct A {
+ constexpr int size() { return 42; } // non-static
+};
+
+template<class T>
+ requires (T::size() == 42) // { dg-error "without object" }
+struct B : T { };
+
+template struct B<A>; // { dg-error "constraint" }
--- /dev/null
+// PR c++/103831
+// { dg-do compile { target c++11 } }
+
+struct A {
+ constexpr int size() { return 42; } // non-static
+};
+
+template<class T>
+struct B : T {
+ static_assert(A::size() == 42, ""); // { dg-error "without object" }
+
+ static int f() {
+ static_assert(A::size() == 42, ""); // { dg-error "without object" }
+ return A::size(); // { dg-error "without object" }
+ }
+
+ int n = A::size();
+ static const int m = A::size(); // { dg-error "without object" }
+};