imp.find_module('test/badsyntax_pep3120') causes segfault

Parser/tokenizer.h

 #ifndef Py_TOKENIZER_H
 #define Py_TOKENIZER_H
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 #include "object.h"
 
 /* Tokenizer interface */
 
@@ skipping 51 matching lines @@
 };
 
 extern struct tok_state *PyTokenizer_FromString(const char *, int);
 extern struct tok_state *PyTokenizer_FromUTF8(const char *, int);
 extern struct tok_state *PyTokenizer_FromFile(FILE *, char*,
                                               char *, char *);
 extern void PyTokenizer_Free(struct tok_state *);
 extern int PyTokenizer_Get(struct tok_state *, char **, char **);
 extern char * PyTokenizer_RestoreEncoding(struct tok_state* tok,
                                           int len, int *offset);
-extern char * PyTokenizer_FindEncoding(int);
+
+/* Get the encoding of a Python file. Check for the coding cookie and check if
+   the file starts with a BOM.
+
+   PyTokenizer_FindEncodingFilename() returns NULL when it can't find the
+   encoding in the first or second line of the file (in which case the encoding
+   should be assumed to be UTF-8).
+
+   The char* returned is malloc'ed via PyMem_MALLOC() and thus must be freed
+   by the caller.
+*/
+extern char* PyTokenizer_FindEncodingFilename(int fd, const char* filename);
+extern char* PyTokenizer_FindEncoding(int fd);
 
 #ifdef __cplusplus
 }
 #endif
 #endif /* !Py_TOKENIZER_H */