From: Nathaniel Shead <nathanieloshead@gmail.com>
Date: Tue, 14 Nov 2023 16:26:03 +0000 (-0500)
Subject: c++: Stream virtual dtor vtable indices
X-Git-Tag: basepoints/gcc-15~4678
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=14979dd31c887ba5ba573f2cdb0647b37e09641a;p=thirdparty%2Fgcc.git

c++: Stream virtual dtor vtable indices

Virtual cloned functions have distinct vtable indices, stream them
explicitly.

As such, this patch ensures that DECL_VINDEX is properly passed on for
cloned functions as well to prevent this from causing issues.

	PR c++/103499

gcc/cp/ChangeLog:

	* module.cc (trees_out::decl_node): Write DECL_VINDEX for
	virtual clones.
	(trees_in::tree_node): Read DECL_VINDEX for virtual clones.

gcc/testsuite/ChangeLog:

	* g++.dg/modules/pr103499_a.C: New test.
	* g++.dg/modules/pr103499_b.C: New test.

Signed-off-by: Nathaniel Shead <nathanieloshead@gmail.com>
Signed-off-by: Nathan Sidwell <nathan@acm.org>
---

diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc
index c1c8c226bc1e..4f5b6e2747a7 100644
--- a/gcc/cp/module.cc
+++ b/gcc/cp/module.cc
@@ -8648,6 +8648,8 @@ trees_out::decl_node (tree decl, walk_kind ref)
 
       tree_node (target);
       tree_node (DECL_NAME (decl));
+      if (DECL_VIRTUAL_P (decl))
+	tree_node (DECL_VINDEX (decl));
       int tag = insert (decl);
       if (streaming_p ())
 	dump (dumper::TREE)
@@ -9869,6 +9871,10 @@ trees_in::tree_node (bool is_use)
 		}
 	  }
 
+	/* A clone might have a different vtable entry.  */
+	if (res && DECL_VIRTUAL_P (res))
+	  DECL_VINDEX (res) = tree_node ();
+
 	if (!res)
 	  set_overrun ();
 	int tag = insert (res);
diff --git a/gcc/testsuite/g++.dg/modules/pr103499_a.C b/gcc/testsuite/g++.dg/modules/pr103499_a.C
new file mode 100644
index 000000000000..0497c2c55044
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/pr103499_a.C
@@ -0,0 +1,12 @@
+// PR c++/103499
+// { dg-module-do compile }
+// { dg-additional-options "-fmodules-ts" }
+// { dg-module-cmi pr103499 }
+
+export module pr103499;
+
+export struct base {
+  virtual ~base() = default;
+};
+
+export struct derived : base {};
diff --git a/gcc/testsuite/g++.dg/modules/pr103499_b.C b/gcc/testsuite/g++.dg/modules/pr103499_b.C
new file mode 100644
index 000000000000..b7468562ba9b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/modules/pr103499_b.C
@@ -0,0 +1,8 @@
+// PR c++/103499
+// { dg-additional-options "-fmodules-ts" }
+
+import pr103499;
+
+void test(derived* p) {
+  delete p;
+}