From c22f3fb780775b91548e32937a3ce1095a7c72a3 Mon Sep 17 00:00:00 2001
From: Tobias Burnus <tobias@codesourcery.com>
Date: Thu, 10 Feb 2022 18:57:37 +0100
Subject: [PATCH] OpenMP/C++: Permit mapping classes with virtual members
 [PR102204]

	PR c++/102204
gcc/cp/ChangeLog:

	* decl2.cc (cp_omp_mappable_type_1): Remove check for virtual
	members as those are permitted since OpenMP 5.0.

libgomp/ChangeLog:

	* testsuite/libgomp.c++/target-virtual-1.C: New test.

gcc/testsuite/ChangeLog:

	* g++.dg/gomp/unmappable-1.C: Remove previously expected dg-message.
---
 gcc/cp/decl2.cc                               |  8 ---
 gcc/testsuite/g++.dg/gomp/unmappable-1.C      |  2 +-
 .../testsuite/libgomp.c++/target-virtual-1.C  | 50 +++++++++++++++++++
 3 files changed, 51 insertions(+), 9 deletions(-)
 create mode 100644 libgomp/testsuite/libgomp.c++/target-virtual-1.C

diff --git a/gcc/cp/decl2.cc b/gcc/cp/decl2.cc
index 78908339989..c6bfcfe631a 100644
--- a/gcc/cp/decl2.cc
+++ b/gcc/cp/decl2.cc
@@ -1540,14 +1540,6 @@ cp_omp_mappable_type_1 (tree type, bool notes)
   /* Arrays have mappable type if the elements have mappable type.  */
   while (TREE_CODE (type) == ARRAY_TYPE)
     type = TREE_TYPE (type);
-  /* A mappable type cannot contain virtual members.  */
-  if (CLASS_TYPE_P (type) && CLASSTYPE_VTABLES (type))
-    {
-      if (notes)
-	inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (type)),
-		"type %qT with virtual members is not mappable", type);
-      result = false;
-    }
   /* All data members must be non-static.  */
   if (CLASS_TYPE_P (type))
     {
diff --git a/gcc/testsuite/g++.dg/gomp/unmappable-1.C b/gcc/testsuite/g++.dg/gomp/unmappable-1.C
index d00ccb5ad79..364f884500c 100644
--- a/gcc/testsuite/g++.dg/gomp/unmappable-1.C
+++ b/gcc/testsuite/g++.dg/gomp/unmappable-1.C
@@ -1,7 +1,7 @@
 /* { dg-do compile } */
 /* { dg-options "-fopenmp" } */
 
-class C /* { dg-message "type .C. with virtual members is not mappable" } */
+class C
 {
 public:
   static int static_member; /* { dg-message "static field .C::static_member. is not mappable" } */
diff --git a/libgomp/testsuite/libgomp.c++/target-virtual-1.C b/libgomp/testsuite/libgomp.c++/target-virtual-1.C
new file mode 100644
index 00000000000..a6ac30e7cf0
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c++/target-virtual-1.C
@@ -0,0 +1,50 @@
+/* { dg-do run } */
+/* Check that classes with virtual member functions works,
+   when using it as declared type. */
+struct base {
+    float data [100];
+
+    base() = default;
+    virtual ~base() = default;
+};
+
+struct derived : public base {
+    int scalar, array[5];
+
+    derived() = default;
+    void do_work ()
+    {
+      int error = 0;
+      #pragma omp target map (tofrom: this[:1], error)
+      {
+	if (scalar != 42 || this->array[0] != 123 || array[4] != 555)
+	  error = 1;
+	if (data[0] != 333 || data[99] != -3)
+	  error = 1;
+	this->scalar = 99;
+	array[0] = 5;
+	array[4] = -4;
+	this->data[0] = 11;
+	this->data[99] = 99;
+      }
+      if (error)
+	__builtin_abort ();
+      if (data[0] != 11 || data[99] != 99)
+	__builtin_abort ();
+      if (scalar != 99 || array[0] != 5 || array[4] != -4)
+	__builtin_abort ();
+    }   
+};
+
+int
+main ()
+{
+  struct derived x;
+  x.data[0] = 333;
+  x.data[99] = -3;
+  x.scalar = 42;
+  x.array[0] = 123;
+  x.array[4] = 555;
+  x.do_work ();
+  return 0;
+}