From d9d34f9a91371dea4bab0b54b2d7f762a6cc23e0 Mon Sep 17 00:00:00 2001
From: Marek Polacek <polacek@redhat.com>
Date: Thu, 5 Sep 2024 13:01:59 -0400
Subject: [PATCH] c++: vtable referring to "unavailable" virtual fn [PR116606]

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;