This has been tested on several platforms, snapshot
200009060345:

NetBSD 1.3.3, gcc 2.7.2.2
NetBSD 1.4.2, egcs 2.91.60
OpenBSD 2.6, gcc 2.95.1

(this bug does not occur on Linux, egcs 2.91.66)

Here's the configure line:

./configure --with-config-file-path=/path/to/valid/php_ini/ \
--enable-debug \
--without-mysql \
--without-gd

php will then crash systematically when launched, the
php.ini is the latest one (although the problem also exist
with 4.0.2 ini file).

Here's what gdb says:

Program received signal SIGSEGV, Segmentation fault.
0x5cba0 in virtual_file_ex (state=0x0, path=0x0, verify_path=0)
    at tsrm_virtual_cwd.c:332
332
(gdb) bt
#0  0x5cba0 in virtual_file_ex (state=0x0, path=0x0,
verify_path=0)
    at tsrm_virtual_cwd.c:332
CWD_STATE_COPY(old_state, state);

I can solve this bug by:
 - compiling without --with-config-file-path, then php
doesn't find any php.ini file and runs 'php -v' fine
(although it displays 4.0.2 but I guess that's another problem)
 - deleting php.ini from the repertory mentioned by
--with-config-file-path, then 'php -v' works.

Sorry if this duplicate with a post to php-dev@ but I
thought it'd be easier to keep track of this bug this way.