Re: [PATCH] c++: xobj fn call without obj [PR115783]

[Jason Merrill]

On 7/6/24 8:22 PM, Patrick Palka wrote:

Bootstrapped and regtested on x86_64-pc-linux-gnu, does this
look OK for trunk/14?

OK.

-- >8 --

The code path for rejecting an object-less call to a non-static
member function should also consider xobj member functions so
that we properly reject the below calls with a "cannot call
member function without object" diagnostic.

        PR c++/115783

gcc/cp/ChangeLog:

        * call.cc (build_new_method_call): Generalize METHOD_TYPE
        check to DECL_OBJECT_MEMBER_FUNCTION_P.

gcc/testsuite/ChangeLog:

        * g++.dg/cpp23/explicit-obj-diagnostics11.C: New test.
---
  gcc/cp/call.cc                                |  2 +-
  .../g++.dg/cpp23/explicit-obj-diagnostics11.C | 48 +++++++++++++++++++
  2 files changed, 49 insertions(+), 1 deletion(-)
  create mode 100644 gcc/testsuite/g++.dg/cpp23/explicit-obj-diagnostics11.C

diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc
index 83070b2f633..41ef7562f27 100644
--- a/gcc/cp/call.cc
+++ b/gcc/cp/call.cc
@@ -11822,7 +11822,7 @@ build_new_method_call (tree instance, tree fns, vec<tree, 
va_gc> **args,
                         fn);
            }

- if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE

+         if (DECL_OBJECT_MEMBER_FUNCTION_P (fn)
              && !DECL_CONSTRUCTOR_P (fn)
              && is_dummy_object (instance))
            {
diff --git a/gcc/testsuite/g++.dg/cpp23/explicit-obj-diagnostics11.C 
b/gcc/testsuite/g++.dg/cpp23/explicit-obj-diagnostics11.C
new file mode 100644
index 00000000000..cc2571f62a2
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp23/explicit-obj-diagnostics11.C
@@ -0,0 +1,48 @@
+// PR c++/115783
+// { dg-do compile { target c++23 } }
+
+struct A {
+  int f(this auto);
+
+  static void s() {
+    f(); // { dg-error "without object" }
+  }
+};
+
+int n = A::f(); // { dg-error "without object" }
+
+struct B {
+  void ns() {
+    A::f(); // { dg-error "without object" }
+  }
+
+  static void s() {
+    A::f(); // { dg-error "without object" }
+  }
+};
+
+template<class T>
+struct C {
+  void ns() {
+    A::f(); // { dg-error "without object" }
+    T::f(); // { dg-error "without object" }
+  }
+
+  static void s() {
+    A::f(); // { dg-error "without object" }
+    T::f(); // { dg-error "without object" }
+  };
+};
+
+template struct C<A>;
+
+template<class T>
+struct D : T {
+  void ns() {
+    A::f(); // { dg-error "without object" }
+    T::f(); // { dg-error "not a member of 'B'" }
+  }
+};
+
+template struct D<B>; // { dg-message "required from here" }
+template struct D<A>; // { dg-bogus "required from here" }