This is the git commit below, with the change to include/openbabel/shared_ptr.h
properly adapted since it originally depends on commit ce178cbb.

The include/openbabel/shared_ptr.h patch was moved to patch-gcc5-support

commit c3abbddae78e654df9322ad1020ff79dd6332946
Author: Matt Swain <m.swain@me.com>
Date:   Thu Oct 31 15:25:53 2013 +0000

    Detect libc++ as this is now the default in OS X Mavericks

diff --git a/include/openbabel/obmolecformat.h b/include/openbabel/obmolecformat.h
index 46ec724..c004313 100644
--- include/openbabel/obmolecformat.h
+++ include/openbabel/obmolecformat.h
@@ -23,7 +23,10 @@ GNU General Public License for more details.
   #include <hash_map>
 #endif
 
-#if __GNUC__ == 4 && __GNUC_MINOR__ >= 1
+#include <ciso646>  // detect std::lib
+#ifdef _LIBCPP_VERSION
+  #include <unordered_map>
+#elif __GNUC__ == 4 && __GNUC_MINOR__ >= 1
   #include <tr1/unordered_map>
 #elif defined(USE_BOOST)
   #include <boost/tr1/unordered_map.hpp>
@@ -141,6 +144,8 @@ public:
 
 #ifdef _MSC_VER
   typedef stdext::hash_map<std::string, unsigned> NameIndexType;
+#elif defined(_LIBCPP_VERSION)
+  typedef std::unordered_map<std::string, unsigned> NameIndexType;
 #elif (__GNUC__ == 4 && __GNUC_MINOR__ >= 1 && !defined(__APPLE_CC__)) || defined (USE_BOOST)
   typedef std::tr1::unordered_map<std::string, unsigned> NameIndexType;
 #else
diff --git a/src/ops/unique.cpp b/src/ops/unique.cpp
index 5f7714f..8527fba 100644
--- src/ops/unique.cpp
+++ src/ops/unique.cpp
@@ -21,7 +21,7 @@ GNU General Public License for more details.
 #include <openbabel/obconversion.h>
 #include <openbabel/descriptor.h>
 #include <openbabel/inchiformat.h>
-#ifdef _MSC_VER
+#if defined(_MSC_VER) || defined(_LIBCPP_VERSION)
   #include <unordered_map>
 #elif (__GNUC__ == 4 && __GNUC_MINOR__ >= 1 && !defined(__APPLE_CC__))
   #include <tr1/unordered_map>
@@ -36,7 +36,11 @@ GNU General Public License for more details.
 
 using namespace std;
 #ifndef NO_UNORDERED_MAP
-using std::tr1::unordered_map;
+  #ifdef _LIBCPP_VERSION
+    using std::unordered_map;
+  #else
+    using std::tr1::unordered_map;
+  #endif
 #endif
 namespace OpenBabel
 {
