diff --git a/libcxxabi/CMakeLists.txt b/libcxxabi/CMakeLists.txt
--- a/libcxxabi/CMakeLists.txt
+++ b/libcxxabi/CMakeLists.txt
@@ -171,6 +171,11 @@
 option(LIBCXXABI_HERMETIC_STATIC_LIBRARY
   "Do not export any symbols from the static library." OFF)
 
+option(LIBCXXABI_RELATIVE_VTABLES_ABI_ENABLED
+  "Use different configurations of libcxxabi functions supported for the \
+  Relative VTables ABI, which replaces vtable function pointers with offsets \
+  between those virtual functions and the vtable itself." OFF)
+
 #===============================================================================
 # Configure System
 #===============================================================================
@@ -470,6 +475,10 @@
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${LIBCXXABI_CXX_FLAGS}")
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${LIBCXXABI_C_FLAGS}")
 
+if (LIBCXXABI_RELATIVE_VTABLES_ABI_ENABLED)
+  add_definitions(-D_LIBCXXABI_RELATIVE_VTABLES_ABI_ENABLED)
+endif()
+
 #===============================================================================
 # Setup Source Code
 #===============================================================================
diff --git a/libcxxabi/src/private_typeinfo.cpp b/libcxxabi/src/private_typeinfo.cpp
--- a/libcxxabi/src/private_typeinfo.cpp
+++ b/libcxxabi/src/private_typeinfo.cpp
@@ -614,10 +614,26 @@
     // Possible future optimization:  Take advantage of src2dst_offset
 
     // Get (dynamic_ptr, dynamic_type) from static_ptr
+#ifdef _LIBCXXABI_RELATIVE_VTABLES_ABI_ENABLED
+    // The vtable address will point to the first virtual function, which is 12
+    // bytes after the start of the vtable (8 for the offset from top + 4 for the typeinfo component).
+    uint8_t* vtable = *reinterpret_cast<uint8_t* const*>(static_ptr);
+    ptrdiff_t offset_to_derived = *(reinterpret_cast<ptrdiff_t*>(vtable - 12));
+
+    const void* dynamic_ptr =
+        static_cast<const char*>(static_ptr) + offset_to_derived;
+
+    // The typeinfo component is now a relative offset to a proxy.
+    int32_t offset_to_ti_proxy = *reinterpret_cast<int32_t*>(vtable - 4);
+    uint8_t* ptr_to_ti_proxy = vtable + offset_to_ti_proxy;
+    const __class_type_info* dynamic_type =
+        *(reinterpret_cast<__class_type_info**>(ptr_to_ti_proxy));
+#else
     void **vtable = *static_cast<void ** const *>(static_ptr);
     ptrdiff_t offset_to_derived = reinterpret_cast<ptrdiff_t>(vtable[-2]);
     const void* dynamic_ptr = static_cast<const char*>(static_ptr) + offset_to_derived;
     const __class_type_info* dynamic_type = static_cast<const __class_type_info*>(vtable[-1]);
+#endif
 
     // Initialize answer to nullptr.  This will be changed from the search
     //    results if a non-null answer is found.  Regardless, this is what will