Index: uspace/lib/cpp/src/internal/runtime.cpp
===================================================================
--- uspace/lib/cpp/src/internal/runtime.cpp	(revision 1b6477e9b3e1882753cf68254b8c679a3e1ce05b)
+++ uspace/lib/cpp/src/internal/runtime.cpp	(revision ef9d098804a0dd5c42f206398eba55ea95569741)
@@ -68,3 +68,10 @@
     __pointer_to_member_type_info::~__pointer_to_member_type_info()
     { /* DUMMY BODY */ }
+
+    extern "C" void* __dynamic_cast(const void* sub, const __class_type_info* src,
+                                    const __class_type_info* dst, std::ptrdiff_t offset)
+    {
+        // TODO: implement
+        return nullptr;
+    }
 }
Index: uspace/lib/cpp/src/internal/unwind.cpp
===================================================================
--- uspace/lib/cpp/src/internal/unwind.cpp	(revision ef9d098804a0dd5c42f206398eba55ea95569741)
+++ uspace/lib/cpp/src/internal/unwind.cpp	(revision ef9d098804a0dd5c42f206398eba55ea95569741)
@@ -0,0 +1,127 @@
+/*
+ * Copyright (c) 2017 Jaroslav Jindrak
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+namespace __cxxabiv1
+{
+    /**
+     * Stack unwinding functionality - Level 1.
+     */
+
+    enum _Unwind_Reason_Code
+    {
+        _URC_NO_REASON                = 0,
+        _URC_FOREIGN_EXCEPTION_CAUGHT = 1,
+        _URC_FATAL_PHASE2_ERROR       = 2,
+        _URC_FATAL_PHASE1_ERROR       = 3,
+        _URC_NORMAL_STOP              = 4,
+        _URC_END_OF_STACK             = 5,
+        _URC_HANDLER_FOUND            = 6,
+        _URC_INSTALL_CONTEXT          = 7,
+        _URC_CONTINUE_UNWIND          = 8
+    };
+
+    struct _Unwind_Exception;
+    using _Unwind_Exception_Cleanup_Fn = void (*)(_Unwind_Reason_Code, _Unwind_Exception*);
+
+    struct _Unwind_Exception
+    {
+        std::uint64_t exception_class;
+        _Unwind_Exception_Cleanup_Fn exception_cleanup;
+        std::uint64_t private_1;
+        std::uint64_t private_2;
+    };
+
+    /* Opaque structure. */
+    struct _Unwind_Context;
+
+    /**
+     * TODO: Explain parameter semantics.
+     */
+    using _Unwind_Stop_Fn = _Unwind_Reason_Code(*)(
+        int, _Unwind_Action, std::uint64_t, _Unwind_Exception*,
+        _Unwind_Context*, void*
+    );
+
+    _Unwind_Reason_Code _Unwind_ForcedUnwind(_Unwind_Exception*, _Unwind_Stop_Fn, void*)
+    {
+        // TODO: implement
+    }
+
+    void _Unwind_Resume(_Unwind_Exception*)
+    {
+        // TODO: implement
+    }
+
+    void _Unwind_DeleteException(_Unwind_Exception*)
+    {
+        // TODO: implement
+    }
+
+    std::uint64_t _Unwind_GetGR(_Unwind_Context*, int)
+    {
+        // TODO: implement
+    }
+
+    void _Unwind_SetGR(_Unwind_Context*, int, std::uint64_t)
+    {
+        // TODO: implement
+    }
+
+    std::uint64_t _Unwind_GetIP(_Unwind_Context*)
+    {
+        // TODO: implement
+    }
+
+    void _Unwind_SetIP(_Unwind_Context*, std::uint64_t)
+    {
+        // TODO: implement
+    }
+
+    std::uint64_t _Unwind_GetLanguageSpecificData(_Unwind_Context*)
+    {
+        // TODO: implement
+    }
+
+    std::uint64_t _Unwind_GetRegionStart(_Unwind_Context*)
+    {
+        // TODO: implement
+    }
+
+    /**
+     * TODO: Explain parameter semantics.
+     */
+    using __personality_routine = _Unwind_Reason_Code(*)(
+        int, _Unwind_Action, std::uint64_t, _Unwind_Exception*,
+        _Unwind_Context*, void*
+    );
+
+    /**
+     * Stack unwinding functionality - Level 2.
+     */
+    // TODO:
+}