Apparently this is not just PDO, it's the majority of the 
extensions, nothing obvious in similarity.  PDO, curl, XSL 
fail, gd and mysql succeeded.  Mysql required editing 
configure to link to libz (or defining LDFLAGS might've 
worked)  So it seems in general the configure/makefile setup 
with PHP extensions in OS X has issues with leaving out the 
compile instructions

What autoconf version are you using?

autoconf 2.59 which i believe is same as my linux machine i 
tested on.

automake is 1.6.3, the linux box was recently switched to 1.8 
due to requirement to build lighttpd web server.  is that a 
possibility?

Please try with autoconf 2.13 and put the result Makefile somewhere in the Net, so we can take a look at it.

I tried autoconf 2.13 by removing the configure file and 
running /sw/bin/autoconf which is where it was installed (thru 
fink), not sure if that's proper enough.  I then ran ./
configure and put the makefile on the internet:

http://www.jeremyknope.com/files/Makefile-pdo-autoconf2.13.txt

I can not access that makefile. Try again?

i apologize, broke the setup for that domain.
http://www.jeremyknope.com/files/Makefile-pdo-autoconf2.13.txt
should work again

Please try using this CVS snapshot:

  http://snaps.php.net/php5.1-latest.tar.gz
 
For Windows:
 
  http://snaps.php.net/win32/php5.1-win32-latest.zip

And make sure you get the right files installed and that you're not mixing new phpize with old build files.

Ok so that seems more successful now, I was able to make 
curl, mysql, xsl, libz, gd on OS X which at least a few 
failed to before with stable 5.1.2

BUT PDO is still failing to generate a proper Makefile. 
Seems couple things are empty that shouldn't be as far as I 
can tell in the Makefile
PHP_MODULES =
all_targets = $(PHP_MODULES)
which fails when make all is run since make all just 
references all targets.

but glad to see every other module seems to be compiling so 
I can make an extension driven install of PHP.

Apparently it's not supposed to be possible to even build PDO as shared extension under MacOSX. Just these Wez's hacks don't work and won't give any warning about it but just silently fails. Wez: Obviously you don't check properly whether phpize is used..

weird, so PDO for some reason is the only one that can't be 
built separately from PHP on OS X? does that include every PDO 
driver? because that'll be a downer.

Please try using this CVS snapshot:

  http://snaps.php.net/php5.2-latest.tar.gz
 
For Windows:
 
  http://snaps.php.net/win32/php5.2-win32-latest.zip

I was unable to try cvs since it failed compiling PHP part 
way through with:

/Users/jerome/Downloads/php5.2-200607181430/Zend/
zend_alloc.c: In function ?zend_mm_mem_mmap_realloc?:
/Users/jerome/Downloads/php5.2-200607181430/Zend/
zend_alloc.c:117: error: ?ret? undeclared (first use in this 
function)
/Users/jerome/Downloads/php5.2-200607181430/Zend/
zend_alloc.c:117: error: (Each undeclared identifier is 
reported only once
/Users/jerome/Downloads/php5.2-200607181430/Zend/
zend_alloc.c:117: error: for each function it appears in.)
make: *** [Zend/zend_alloc.lo] Error 1

The next snapshot should be ok.
Thanks for the alert.

I just grabbed PHP 5.2 CVS 200607181630 snapshot and attempted 
to compile it, PHP itself compiled fine, but PDO still does 
not generate a proper makefile on Mac OS X.

after running the php5.2cvs's phpize on ext/pdo, i did 
configure then make, and it just immediately thinks it's done 
like it always has been doing.

Due to the way that loadable modules work on OSX/Darwin, you need to compile the PDO package statically into the PHP core.
I've fixed the configure, so it will fail if you try to compile PDO dynamically.

After some looking into, I reopened this bug after discussing this 
with mac developers and the fact being stated that OS X has dlopen and 
friends just like linux.  ALso the fact that MOST of the php 
extensions build fine on OS X except for PDO and maybe one or 2 
others.

This doesn't seem reasonable to not be able to do, if other extensions 
can be compiled & loaded, why can't PDO.  it really limits options 
like considering Zend Core when you can't install PDO via pecl.

Quick comment, clarification of dlopen() if that applies to this.  OS 
X 10.3.x supposedly has a dl compat layer, where 10.4.x actually has 
native support for dlopen() and friends.

I removed the restriction in configure and compiled both PDO and PDO_SQLITE as shared.
This is what I get after enabling both of them (first PDO, then PDO_SQLITE):

dyld: lazy symbol binding failed: Symbol not found: _php_pdo_register_driver
  Referenced from: /var/root/tony/php-src_5_2/modules/pdo_sqlite.so
  Expected in: flat namespace

dyld: Symbol not found: _php_pdo_register_driver
  Referenced from: /var/root/tony/php-src_5_2/modules/pdo_sqlite.so
  Expected in: flat namespace

Trace/BPT trap

So it seems dynamic linker is still broken in MacOSX, therefor the restriction is reasonable.

_php_pdo_register_driver is defined in pdo.so i believe right?
So pdo_sqlite should be linking against the pdo.so extension?

How do I disable configure restriction so I can try this out and get 
more information to some smarter mac devs than myself?  I've been 
giving this info to them and they still seem to think something isn't 
being linked that it should work.

Is this an issue with the latest 5.x release?

No feedback was provided. The bug is being suspended because
we assume that you are no longer experiencing the problem.
If this is not the case and you are able to provide the
information that was requested earlier, please do so and
change the status of the bug back to "Re-Opened". Thank you.