Any script that contains a call to the parse_ini_file() function results in a segmentation fault. This is the case for mod_php4 and the CLI. The scripts used to test this are at http://jodrell.net/files/parse_ini_file_bug/

Here's what happens when the script is run from a shell:

[root@spoon rael]# /usr/local/bin/php parse_ini_file_demo.php 
Date: Tue, 20 May 2003 10:37:09 +0100
This string is printed before parsing.
Segmentation fault (core dumped)


[root@spoon rael]# gdb /usr/local/bin/php core
GNU gdb Red Hat Linux (5.2-2)
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This GDB was configured as "i386-redhat-linux"...
Core was generated by `/usr/local/bin/php parse_ini_file_demo.php'.
Program terminated with signal 11, Segmentation fault.
Reading symbols from /lib/libcrypt.so.1...done.
Loaded symbols for /lib/libcrypt.so.1
Reading symbols from /lib/libresolv.so.2...done.
Loaded symbols for /lib/libresolv.so.2
Reading symbols from /lib/i686/libm.so.6...done.
Loaded symbols for /lib/i686/libm.so.6
Reading symbols from /lib/libdl.so.2...done.
Loaded symbols for /lib/libdl.so.2
Reading symbols from /lib/libnsl.so.1...done.
Loaded symbols for /lib/libnsl.so.1
Reading symbols from /lib/i686/libc.so.6...done.
Loaded symbols for /lib/i686/libc.so.6
Reading symbols from /lib/ld-linux.so.2...done.
Loaded symbols for /lib/ld-linux.so.2
Reading symbols from /lib/libnss_files.so.2...done.
Loaded symbols for /lib/libnss_files.so.2
#0  0x4011a3cd in __libc_free (mem=0xbfffca4c) at malloc.c:3143
3143    malloc.c: No such file or directory.
        in malloc.c
(gdb) bt
#0  0x4011a3cd in __libc_free (mem=0xbfffca4c) at malloc.c:3143
#1  0x0810e798 in _efree (ptr=0xbfffca58)
    at /home/stuff/php-4.3.2RC3/Zend/zend_alloc.c:265
#2  0x08108cb2 in zend_file_handle_dtor (fh=0xbfffca20)
    at Zend/zend_language_scanner.c:2945
#3  0x0810cd78 in zend_parse_ini_file (fh=0xbfffca20, unbuffered_errors=0, 
    ini_parser_cb=0x8094b94 <php_simple_ini_parser_cb>, arg=0x81a9e3c)
    at Zend/zend_ini_parser.c:185
#4  0x08094f0e in zif_parse_ini_file (ht=1, return_value=0x81a9e3c, 
    this_ptr=0x0, return_value_used=1)
    at /home/stuff/php-4.3.2RC3/ext/standard/basic_functions.c:2894
#5  0x0812fb88 in execute (op_array=0x81a57cc)
    at /home/stuff/php-4.3.2RC3/Zend/zend_execute.c:1606
#6  0x0811d60c in zend_execute_scripts (type=8, retval=0x0, file_count=3)
    at /home/stuff/php-4.3.2RC3/Zend/zend.c:886
#7  0x080f6c9c in php_execute_script (primary_file=0xbffff5b0)
    at /home/stuff/php-4.3.2RC3/main/main.c:1687
#8  0x08138314 in main (argc=2, argv=0xbffff654)
    at /home/stuff/php-4.3.2RC3/sapi/cli/php_cli.c:805
#9  0x400b5657 in __libc_start_main (main=0x81378a0 <main>, argc=2, 
    ubp_av=0xbffff654, init=0x8060eec <_init>, fini=0x81388c0 <_fini>, 
    rtld_fini=0x4000dcd4 <_dl_fini>, stack_end=0xbffff64c)
    at ../sysdeps/generic/libc-start.c:129