From 362114a95855497568694c59cb0f5a72d2c30d29 Mon Sep 17 00:00:00 2001
From: Morgan Deters <mdeters@cs.nyu.edu>
Date: Tue, 12 Nov 2013 18:12:11 -0500
Subject: [PATCH] Some additional explanation for a common configure error.

---
 configure.ac | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 1859d6316..1aad3ab6c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -762,7 +762,13 @@ typedef pb_ds::priority_queue<void, void, void> pq;])],
     #include <ext/pb_ds/priority_queue.hpp>
     typedef __gnu_pbds::priority_queue<void, void, void> pq;])],
       [CVC4_PB_DS_NAMESPACE=__gnu_pbds],
-      [AC_MSG_ERROR([cannot find required priority_queue in either __gnu_pbds or pb_ds namespace])])])
+      [AC_MSG_ERROR([cannot find required priority_queue in either __gnu_pbds or pb_ds namespace.
+
+If you're using a non-GCC compiler (such as clang), you may need to explicitly
+use the GNU standard C++ library by passing:
+    CXXFLAGS='-stdlib=libstdc++'
+as an argument to this configure script.
+This is the case on Mac OS Mavericks, for example.])])])
 AC_LANG_POP([C++])
 AC_MSG_RESULT([$CVC4_PB_DS_NAMESPACE])
 AC_DEFINE_UNQUOTED(CVC4_PB_DS_NAMESPACE, ${CVC4_PB_DS_NAMESPACE}, [The namespace for pb_ds data structures.])
-- 
2.30.2