Bug 33221 [UBSAN] segfault with -fsanitize=undefined

There is can be a situation when vptr is not initializing
by constructor of the object, and has a junk data which should
be properly checked, because c++ standard says:

"if default constructor is not specified
16 (7.3) no initialization is performed."

Patch by Denis Khalikov!

Differential Revision: https://reviews.llvm.org/D33712

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@304437 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 24 insertions, 0 deletions

diff --git a/test/ubsan/TestCases/TypeCheck/PR33221.cpp b/test/ubsan/TestCases/TypeCheck/PR33221.cpp
new file mode 100644
index 000000000..17e35a6d9
--- /dev/null
+++ b/test/ubsan/TestCases/TypeCheck/PR33221.cpp
@@ -0,0 +1,24 @@
+// RUN: %clangxx -frtti -fsanitize=undefined -g %s -O3 -o %t
+// RUN: %run %t 2>&1 | FileCheck %s
+
+// REQUIRES: cxxabi
+
+class Base {
+public:
+  int i;
+  virtual void print() {}
+};
+
+class Derived : public Base {
+public:
+  void print() {}
+};
+
+int main() {
+  Derived *list = (Derived *)new char[sizeof(Derived)];
+
+// CHECK: PR33221.cpp:[[@LINE+2]]:19: runtime error: member access within address {{.*}} which does not point to an object of type 'Base'
+// CHECK-NEXT: object has invalid vptr
+  int foo = list->i;
+  return 0;
+}