From 6700290a3eca05c172fe45879b225cf4dbc0693e Mon Sep 17 00:00:00 2001
From: Douglas Gregor <doug.gregor@gmail.com>
Date: Sun, 24 Sep 2006 12:36:22 +0000
Subject: [PATCH] Fix linking of libboost_python on Mac OS X

[SVN r35307]
---
 src/tools/python.jam | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/src/tools/python.jam b/src/tools/python.jam
index 5c5b14546..aa819e9a3 100644
--- a/src/tools/python.jam
+++ b/src/tools/python.jam
@@ -363,19 +363,20 @@ rule init-mac ( version : root ? : includes ? : libraries ? )
     }
     PYTHON_FRAMEWORK = $(PYTHON_FRAMEWORK:D)/Python ;
 
-    alias python_for_extensions
-      : 
-      :
-      : 
-      : <include>$(includes)
-      ;  
-    
     alias python
       :
       : <os>MACOSX <toolset>darwin
       :
       : <include>$(includes) <framework>$(PYTHON_FRAMEWORK)
       ;  
+
+    # Unlike most *nix systems, Mac OS X's linker does not permit undefined
+    # symbols when linking a shared library. So, we still need to link
+    # against the Python framework, even when building extensions. 
+    # Note that framework builds of Python always use shared libraries,
+    # so we do not need to worry about duplicate Python symbols.
+    .alias-defined = true ;
+    alias python_for_extensions : python ;
 }
 
 rule init-nt ( version : root ? : includes ? : libraries ? : cygwin-condition ? )