patch for re.sub bug, by AMK.

Modules/pcre.h

@@ -57,11 +57,13 @@ extern void  (*pcre_free)(void *);
 
 #ifdef FOR_PYTHON
 extern pcre *pcre_compile(const char *, int, const char **, int *, PyObject *);
+extern int pcre_exec(const pcre *, const pcre_extra *, const char *,
+  int, int, int, int *, int);
 #else
 extern pcre *pcre_compile(const char *, int, const char **, int *);
-#endif
 extern int pcre_exec(const pcre *, const pcre_extra *, const char *,
   int, int, int *, int);
+#endif
 extern int pcre_info(const pcre *, int *, int *);
 extern pcre_extra *pcre_study(const pcre *, int, const char **);
 extern const char *pcre_version(void);

Modules/pcremodule.c

@@ -115,7 +115,7 @@ PyPcre_exec(self, args)
 		return NULL;
 	if (endpos == -1) {endpos = stringlen;}
 	count = pcre_exec(self->regex, self->regex_extra, 
-			  (char *)string+pos, endpos - pos, options,
+			  (char *)string, endpos, pos, options,
 			  offsets, sizeof(offsets)/sizeof(int) );
 	/* If an error occurred during the match, and an exception was raised,
 	   just return NULL and leave the exception alone.  The most likely
@@ -143,8 +143,6 @@ PyPcre_exec(self, args)
 		/* If the group wasn't affected by the match, return -1, -1 */
 		if (start<0 || count<=i) 
 		{start=end=-1;}
-		else 
-		{start += pos; end +=pos;}
 		v=Py_BuildValue("ii", start, end);
 		if (v==NULL) {Py_DECREF(list); return NULL;}
 		PyList_SetItem(list, i, v);

Modules/pypcre.c

@@ -4424,7 +4424,8 @@ Returns:          > 0 => success; value is the number of elements filled in
 
 int
 pcre_exec(const pcre *external_re, const pcre_extra *external_extra,
-  const char *subject, int length, int options, int *offsets, int offsetcount)
+  const char *subject, int length, int start_pos, int options, 
+  int *offsets, int offsetcount)
 {
   /* The "volatile" directives are to make gcc -Wall stop complaining
      that these variables can be clobbered by the longjmp.  Hopefully
@@ -4433,7 +4434,7 @@ int resetcount, ocount;
 int first_char = -1;
 match_data match_block;
 const uschar *start_bits = NULL;
-const uschar *start_match = (const uschar *)subject;
+const uschar *start_match = (const uschar *)subject + start_pos;
 const uschar *end_subject;
 const real_pcre *re = (const real_pcre *)external_re;
 const real_pcre_extra *extra = (const real_pcre_extra *)external_extra;