Patch #1232023: Don't include empty path component from registry,

so that the current directory does not get added to sys.path.
Also fixes #1526785.

Misc/NEWS

@@ -12,6 +12,9 @@ What's New in Python 2.5 release candidate 1?
 Core and builtins
 -----------------
 
+- Patch #1232023: Stop including current directory in search
+  path on Windows.
+
 - Fix some potential crashes found with failmalloc.
 
 - Fix warnings reported by Klocwork's static analysis tool.

PC/getpathp.c

@@ -297,6 +297,10 @@ getpythonregpath(HKEY keyBase, int skipcore)
 		}
 		RegCloseKey(subKey);
 	}
+
+	/* return null if no path to return */
+	if (dataSize == 0) goto done;
+
 	/* original datasize from RegQueryInfo doesn't include the \0 */
 	dataBuf = malloc((dataSize+1) * sizeof(TCHAR));
 	if (dataBuf) {