Re: [PATCH] c++: vtable referring to "unavailable" virtual fn [PR116606]

[Jason Merrill]

On 9/5/24 2:28 PM, Marek Polacek wrote:

Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk?

OK.

-- >8 --
mark_vtable_entries already has

    /* It's OK for the vtable to refer to deprecated virtual functions.  */
    warning_sentinel w(warn_deprecated_decl);

but that doesn't cover __attribute__((unavailable)).  We can use the
following override to cover both.

        PR c++/116606

gcc/cp/ChangeLog:

        * decl2.cc (mark_vtable_entries): Temporarily override deprecated_state 
to
        UNAVAILABLE_DEPRECATED_SUPPRESS.  Remove a warning_sentinel.

gcc/testsuite/ChangeLog:

        * g++.dg/ext/attr-unavailable-13.C: New test.
---
  gcc/cp/decl2.cc                                | 3 ++-
  gcc/testsuite/g++.dg/ext/attr-unavailable-13.C | 8 ++++++++
  2 files changed, 10 insertions(+), 1 deletion(-)
  create mode 100644 gcc/testsuite/g++.dg/ext/attr-unavailable-13.C

diff --git a/gcc/cp/decl2.cc b/gcc/cp/decl2.cc
index 3c4f34868ee..0279372488c 100644
--- a/gcc/cp/decl2.cc
+++ b/gcc/cp/decl2.cc
@@ -2180,7 +2180,8 @@ static void
  mark_vtable_entries (tree decl, vec<tree> &consteval_vtables)
  {
    /* It's OK for the vtable to refer to deprecated virtual functions.  */
-  warning_sentinel w(warn_deprecated_decl);
+  auto du = make_temp_override (deprecated_state,
+                               UNAVAILABLE_DEPRECATED_SUPPRESS);

bool consteval_seen = false; diff --git a/gcc/testsuite/g++.dg/ext/attr-unavailable-13.C b/gcc/testsuite/g++.dg/ext/attr-unavailable-13.C

new file mode 100644
index 00000000000..9ca40005419
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/attr-unavailable-13.C
@@ -0,0 +1,8 @@
+// PR c++/116606
+// { dg-do compile }
+
+struct C {
+    __attribute__((unavailable)) virtual void f() {}
+};
+
+C c;

base-commit: c880fca6cdb16c5efe3a12ee7ecdb2435f5e7105