Description:
------------
The fix for bug #21310 introduced:
#if HAVE_BROKEN_GETCWD
                        /* this looks nasty to me */
                        old_cwd_fd = open(".", 0);
                        if (old_cwd_fd == -1) {
                                zend_bailout();
                        }

into php_execute_script in main/main.c.

If PHP does not have read permissions on the cwd, it bails out and the client gets an empty response body.

This is a particular problem if the last request has chdir'd the web server to such a directory. Apache does this when you request a file that uses server side includes.

Reproduce code:
---------------
# mkdir -m 711 /tmp/abc
# cd /tmp/abc
# httpd -X
$ wget -q -O - http://localhost/content.php

# httpd -X
$ wget -q -O - http://localhost/no_read_perms/content.shtml
$ wget -q -O - http://localhost/content.php


Expected result:
----------------
$ wget -q -O - http://localhost/content.php
  ...
$

$ wget -q -O - http://localhost/no_read_perms/content.shtml
  ...
$ wget -q -O - http://localhost/content.php
  ...
$


Actual result:
--------------
$ wget -q -O - http://localhost/content.php
$

$ wget -q -O - http://localhost/no_read_perms/content.shtml
  ...
$ wget -q -O - http://localhost/content.php
$