[libcxxabi] Introduce a -fno-exceptions libc++abi libary variant

Currently there is only support for a -fno-exceptions libc++ build. This is
problematic for functions such as std::terminate() which are defined in
libc++abi and using any of those functions throws away most of the benefits
of using -fno-exceptions (code-size). This patch introduces a -fno-exceptions
libc++abi build to address this issue.

This new variant of libc++abi cannot be linked against any with-exceptions
code as some symbols necessary for handling exceptions are missing in this
library.

Differential revision: http://reviews.llvm.org/D20677

Reviewers: EricWF, mclow.lists, bcraig
llvm-svn: 271267

1 files changed, 55 insertions, 0 deletions

diff --git a/libcxxabi/test/cxa_bad_cast.pass.cpp b/libcxxabi/test/cxa_bad_cast.pass.cpp
new file mode 100644
index 00000000000..c863d6f3ffe
--- /dev/null
+++ b/libcxxabi/test/cxa_bad_cast.pass.cpp
@@ -0,0 +1,55 @@
+//===----------------------- cxa_bad_cast.pass.cpp ------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03
+
+#include <cxxabi.h>
+#include <cassert>
+#include <stdlib.h>
+#include <exception>
+#include <typeinfo>
+
+class Base {
+  virtual void foo() {};
+};
+
+class Derived : public Base {};
+
+Derived &test_bad_cast(Base b) {
+  return dynamic_cast<Derived&>(b);
+}
+
+Base gB;
+
+void my_terminate() { exit(0); }
+
+int main ()
+{
+    // swap-out the terminate handler
+    void (*default_handler)() = std::get_terminate(); 
+    std::set_terminate(my_terminate);
+
+#ifndef LIBCXXABI_HAS_NO_EXCEPTIONS
+    try {
+#endif
+        Derived &d = test_bad_cast(gB);
+        assert(false);
+#ifndef LIBCXXABI_HAS_NO_EXCEPTIONS
+    } catch (std::bad_cast) {
+        // success
+        return 0;
+    } catch (...) {
+        assert(false);
+    }
+#endif
+
+    // failure, restore the default terminate handler and fire
+    std::set_terminate(default_handler);
+    std::terminate();
+}