Polish cimport from pyx.

Cython/Compiler/ModuleNode.py

@@ -2115,7 +2115,9 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         # Generate code to create PyCFunction wrappers for exported C functions.
         entries = []
         for entry in env.var_entries:
-            if entry.api or entry.defined_in_pxd or Options.cimport_from_pyx:
+            if (entry.api
+                or entry.defined_in_pxd
+                or (Options.cimport_from_pyx and not entry.visibility == 'extern')):
                 entries.append(entry)
         if entries:
             env.use_utility_code(voidptr_export_utility_code)
@@ -2129,7 +2131,9 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         # Generate code to create PyCFunction wrappers for exported C functions.
         entries = []
         for entry in env.cfunc_entries:
-            if entry.api or entry.defined_in_pxd or Options.cimport_from_pyx:
+            if (entry.api
+                or entry.defined_in_pxd
+                or (Options.cimport_from_pyx and not entry.visibility == 'extern')):
                 entries.append(entry)
         if entries:
             env.use_utility_code(function_export_utility_code)

Cython/Compiler/Symtab.py

@@ -1078,6 +1078,8 @@ class ModuleScope(Scope):
             self.var_entries.append(entry)
         else:
             entry.is_pyglobal = 1
+        if Options.cimport_from_pyx:
+            entry.used = 1
         return entry
 
     def declare_cfunction(self, name, type, pos,