dyncast.cc (__dynamic_cast): Handle mid-destruction dynamic_cast more gracefully.

	* libsupc++/dyncast.cc (__dynamic_cast): Handle mid-destruction
	dynamic_cast more gracefully.

From-SVN: r215350

1 files changed, 28 insertions, 0 deletions

diff --git a/gcc/testsuite/g++.dg/rtti/dyncast7.C b/gcc/testsuite/g++.dg/rtti/dyncast7.C
new file mode 100644
index 0000000..deb4397
--- /dev/null
+++ b/gcc/testsuite/g++.dg/rtti/dyncast7.C
@@ -0,0 +1,28 @@
+// I think this dynamic_cast has undefined behavior when destroying E::o
+// because we're the F period of destruction has started and ap doesn't
+// point to the object currently being destroyed--but the reasonable
+// options are success or failure, not SEGV.
+
+// { dg-do run }
+
+extern "C" void abort();
+
+struct A { virtual ~A(); };
+struct B { virtual ~B() { } };
+struct C : B, A { };
+struct E : virtual B { A o; };
+struct F : virtual C, virtual E { };
+
+A* ap;
+C* cp;
+
+A::~A() {
+  C* cp2 = dynamic_cast<C*>(ap);
+  if (cp2 != cp && cp2 != 0)
+    abort();
+}
+
+int main() {
+  F f;
+  ap = cp = &f;
+}