Here during satisfaction of B's associated 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 bases, and so the
any_dependent_bases_p check within build_new_method_call causes us to
avoid rejecting the call.

This patch fixes this by refining the any_dependent_bases_p check within
build_new_method_call: dependent bases can't make a difference for
resolving the implicit object parameter if we're in a conext where
'this' is unavailable, so let's check current_class_ptr too.

Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
trunk and perhaps 11?  The first testcase exhibits a regression
introduced by r12-1937.

        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.
---
 gcc/cp/call.c                                 |  2 +-
 gcc/testsuite/g++.dg/cpp2a/concepts-class3.C  | 12 ++++++++++++
 .../g++.dg/template/non-dependent18.C         | 19 +++++++++++++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp2a/concepts-class3.C
 create mode 100644 gcc/testsuite/g++.dg/template/non-dependent18.C

diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index bee367f57d7..3da9e7a6284 100644
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -11098,7 +11098,7 @@ build_new_method_call (tree instance, tree fns, 
vec<tree, va_gc> **args,
                     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
diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-class3.C 
b/gcc/testsuite/g++.dg/cpp2a/concepts-class3.C
new file mode 100644
index 00000000000..68b50b71278
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/concepts-class3.C
@@ -0,0 +1,12 @@
+// 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" }
diff --git a/gcc/testsuite/g++.dg/template/non-dependent18.C 
b/gcc/testsuite/g++.dg/template/non-dependent18.C
new file mode 100644
index 00000000000..7fe623d497f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/non-dependent18.C
@@ -0,0 +1,19 @@
+// 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" }
+};
-- 
2.34.1.390.g2ae0a9cb82

Reply via email to