diff -r 7bc53cf8b2df Include/pymacro.h
--- a/Include/pymacro.h	Mon Aug 04 11:18:23 2014 -0500
+++ b/Include/pymacro.h	Mon Aug 04 15:37:20 2014 -0500
@@ -63,8 +63,10 @@
 #define PyDoc_VAR(name) static char name[]
 #define PyDoc_STRVAR(name,str) PyDoc_VAR(name) = PyDoc_STR(str)
 #ifdef WITH_DOC_STRINGS
+#define PyDoc_VAR_WITH_SIZE(name, size) static char name[size]
 #define PyDoc_STR(str) str
 #else
+#define PyDoc_VAR_WITH_SIZE(name, size) static char name[1]
 #define PyDoc_STR(str) ""
 #endif
 
diff -r 7bc53cf8b2df Tools/clinic/clinic.py
--- a/Tools/clinic/clinic.py	Mon Aug 04 11:18:23 2014 -0500
+++ b/Tools/clinic/clinic.py	Mon Aug 04 15:37:20 2014 -0500
@@ -616,7 +616,7 @@
             docstring_prototype = docstring_definition = ''
         else:
             docstring_prototype = normalize_snippet("""
-                PyDoc_VAR({c_basename}__doc__);
+                PyDoc_VAR_WITH_SIZE({c_basename}__doc__, {docstring_size});
                 """)
             docstring_definition = normalize_snippet("""
                 PyDoc_STRVAR({c_basename}__doc__,
@@ -1049,6 +1049,7 @@
         template_dict['methoddef_name'] = methoddef_name
 
         template_dict['docstring'] = self.docstring_for_c_string(f)
+        template_dict['docstring_size'] = len(f.docstring) + 1
 
         template_dict['self_name'] = template_dict['self_type'] = template_dict['self_type_check'] = ''
         f_self.converter.set_template_dict(template_dict)