From:             [EMAIL PROTECTED]
Operating system: Windows 2000
PHP version:      4.3.0RC1
PHP Bug Type:     BC math related
Bug description:  BC Math is not Thread Safe, but is in Win32 TS distribution

I'm adding this bug report to make sure it doesn't get lost.  I would ask
that this be marked critial for 4.3.0 release.  The current thread safe
Win32 build is _not_ thread safe because it includes BC Math as a built-in
extension, but BC Math is not thread safe.

Here is what I said on the php-dev list:
 
> > I'm seeing a memory overrun under PHP 4.3.0pre2 (debug) running under
> > Windows 2000 ISAPI.  [ . . . ]
> > ---------------------------------------
> > C:\Work\php-source\php-4.3.0pre2\ext\bcmath\libbcmath\src\init.c(72):
> > Freeing 0x01B85050 (1 bytes), script=c:\inetpub\wwwroot\test.php
> > Last leak repeated 2 times
> > C:\Work\php-source\php-4.3.0pre2\ext\bcmath\libbcmath\src\init.c(57):
> > Freeing 0x01B84FF8 (29 bytes), script=c:\inetpub\wwwroot\test.php
> > Last leak repeated 2 times
>
>Based on seeing these leaks I disabled BCMath and recompiled PHP.
>Without BCMath active I do not have any of the memory overruns that I
>reported in my previous message.
>
>Looking in the CVS logs for php4/ext/bcmath/bcmath.c I believe there
>may be an issue with the changes introduced in version 1.37 (by Andi,
>who is CCed also).  This patch moved the allocation and freeing of the
>static BC numbers _zero_, _one_, and _two_ to a per-request basis
>instead of at module initilzation and shutdown.  It looks like the
>storage locations for those values are global externs, however, which
>multiple threads are now allocating and deallocating at the same time.
>
>Is there somewhere that I'm not understanding in the code that would
>keep multiple threads from smashing each other here?

And these were Andi's responses:

> > You are right. I screwed up. I have to make these TSRM globals.
> > I'll try and do it tomorrow.
>
> Adding a BCMATH_G() TSRM macro around all instances of _one_, _two_ and

> _zero_ seems to be quite a pain because it means that libbcmath needs to

> understand TSRM now.
> On the other hand these three variables need to be per-request because 
> emalloc()'ed memory can't survive in between requests.
> Does anyone have any interesting solutions? If not I guess we can start

> hacking at the libbcmath sources.
-- 
Edit bug report at http://bugs.php.net/?id=20495&edit=1
-- 
Try a CVS snapshot:         http://bugs.php.net/fix.php?id=20495&r=trysnapshot
Fixed in CVS:               http://bugs.php.net/fix.php?id=20495&r=fixedcvs
Fixed in release:           http://bugs.php.net/fix.php?id=20495&r=alreadyfixed
Need backtrace:             http://bugs.php.net/fix.php?id=20495&r=needtrace
Try newer version:          http://bugs.php.net/fix.php?id=20495&r=oldversion
Not developer issue:        http://bugs.php.net/fix.php?id=20495&r=support
Expected behavior:          http://bugs.php.net/fix.php?id=20495&r=notwrong
Not enough info:            http://bugs.php.net/fix.php?id=20495&r=notenoughinfo
Submitted twice:            http://bugs.php.net/fix.php?id=20495&r=submittedtwice
register_globals:           http://bugs.php.net/fix.php?id=20495&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=20495&r=php3
Daylight Savings:           http://bugs.php.net/fix.php?id=20495&r=dst
IIS Stability:              http://bugs.php.net/fix.php?id=20495&r=isapi

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