From: Stefan Behnel <scoder@users.berlios.de>
Date: Wed, 3 Nov 2010 20:24:09 +0000 (+0100)
Subject: make sure the cname really is unique when overriding its signature
X-Git-Tag: 0.14.alpha0~236
X-Git-Url: http://git.tremily.us/gitweb.cgi?a=commitdiff_plain;h=9abfe020a45d5737b744602490a5566ca738fbc4;p=cython.git

make sure the cname really is unique when overriding its signature
---

diff --git a/Cython/Compiler/Symtab.py b/Cython/Compiler/Symtab.py
index 8f176c8e..fb84b836 100644
--- a/Cython/Compiler/Symtab.py
+++ b/Cython/Compiler/Symtab.py
@@ -552,7 +552,18 @@ class Scope(object):
                 warning(pos, "Function '%s' previously declared as '%s'" % (name, entry.visibility), 1)
             if not entry.type.same_as(type):
                 if visibility == 'extern' and entry.visibility == 'extern':
-                    if self.is_cpp() or (cname and entry.cname and cname != entry.cname):
+                    can_override = False
+                    if self.is_cpp():
+                        can_override = True
+                    elif cname:
+                        # if all alternatives have different cnames,
+                        # it's safe to allow signature overrides
+                        for alt_entry in entry.all_alternatives():
+                            if not alt_entry.cname or cname == alt_entry.cname:
+                                break # cname not unique!
+                        else:
+                            can_override = True
+                    if can_override:
                         temp = self.add_cfunction(name, type, pos, cname, visibility, modifiers)
                         temp.overloaded_alternatives = entry.all_alternatives()
                         entry = temp