Fix cpdef, make corrupt c file older than pyx file.

Cython/Compiler/Symtab.py

@@ -375,7 +375,7 @@ class Scope:
     def declare_pyfunction(self, name, pos):
         # Add an entry for a Python function.
         entry = self.lookup_here(name)
-        if entry:
+        if entry and not entry.type.is_cfunction:
             # This is legal Python, but for now will produce invalid C.
             error(pos, "'%s' already declared" % name)
         entry = self.declare_var(name, py_object_type, pos)

Cython/Utils.py

@@ -30,7 +30,7 @@ def castrate_file(path, st):
             "#error Do not use this file, it is the result of a failed Cython compilation.\n")
         f.close()
         if st:
-            os.utime(path, (st.st_atime, st.st_mtime))
+            os.utime(path, (st.st_atime, st.st_mtime-1))
 
 def modification_time(path):
     st = os.stat(path)

tests/compile/cpdef.pyx

+cdef class A:
+    cpdef a(self):
+        ma(self)
+
+cpdef ma(x):
+    print x