Description:
------------
PHP segfaults when calling phpinfo() with output buffering started. If the call to ob_start() is left out, the code works fine.

I really don't know how to interpret the backtrace, but if I'm correct, the problem is in the Standard PHP Library (SPL). On line 109 of spl_functions.c, there is a call to strlen() with the parameter pce->name. However, according to the backtrace, pce equals 0x0. Could this be what is causing the problem?

To test my assumption, I recompiled PHP with --disable-spl and the segfault no longer occurs. How output buffering comes into the picture is beyond me.

Reproduce code:
---------------
<?php

ob_start();
phpinfo();

?>

Expected result:
----------------
phpinfo() should be displayed.

Actual result:
--------------
(gdb) bt
#0  spl_add_class_name (list=0xbfffd5cc, pce=0x0, allow=1, ce_flags=8)
    at /root/src/php5-200402051830/ext/spl/spl_functions.c:109
#1  0x08098b5a in spl_add_classes (ppce=0x81f6028, list=0xbfffd5cc, sub=0,
    allow=1, ce_flags=8)
    at /root/src/php5-200402051830/ext/spl/spl_functions.c:141
#2  0x0809832d in zm_info_spl (zend_module=0x825f888)
    at /root/src/php5-200402051830/ext/spl/php_spl.c:205
#3  0x08103f44 in _display_module_info (module=0x825f888, arg=0xbfffd6d0)
    at /root/src/php5-200402051830/ext/standard/info.c:76
#4  0x08182bbe in zend_hash_apply_with_argument (ht=0xbfffd728,
    apply_func=0x8103ed4 <_display_module_info>, argument=0xbfffd6d0)
    at /root/src/php5-200402051830/Zend/zend_hash.c:677
#5  0x0810582e in php_print_info (flag=-1)
    at /root/src/php5-200402051830/ext/standard/info.c:562
#6  0x08106ebe in zif_phpinfo (ht=0, return_value=0x4022177c, this_ptr=0x0,
    return_value_used=0) at /root/src/php5-200402051830/ext/standard/info.c:882
#7  0x081b58ff in zend_do_fcall_common_helper (execute_data=0xbfffd8b0,
    opline=0x40221d58, op_array=0x40221b94)
    at /root/src/php5-200402051830/Zend/zend_execute.c:2560
#8  0x081b607d in zend_do_fcall_handler (execute_data=0xbfffd8b0,
    opline=0x40221d58, op_array=0x40221b94)
    at /root/src/php5-200402051830/Zend/zend_execute.c:2700
#9  0x0819b13f in execute (op_array=0x40221b94)
    at /root/src/php5-200402051830/Zend/zend_execute.c:1272
#10 0x0817c13c in zend_execute_scripts (type=8, retval=0x0, file_count=3)
    at /root/src/php5-200402051830/Zend/zend.c:1051
#11 0x08146585 in php_execute_script (primary_file=0xbffffc3c)
    at /root/src/php5-200402051830/main/main.c:1641
#12 0x081bfba4 in main (argc=2, argv=0xbffffcc4)
    at /root/src/php5-200402051830/sapi/cli/php_cli.c:941
#13 0x401083c1 in __libc_start_main () from /lib/libc.so.6