(Remove 2.2250738585072012e-308 from my list of examples; it does NOT map to the same floating-point number as 2.2250738585072011e-308 -- when converted correctly!)

Dmitry, can you take a look at it please?

I also get the same problem on Linux (PHP Version 5.3.2-1ubuntu4.5).

Doesn't happen on a mac.

$ php -v
PHP 5.3.1 (cli) (built: Feb 11 2010 02:32:22) 
Copyright (c) 1997-2009 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2009 Zend Technologies

$ php -r "print 2.2250738585072011e-308;"
2.2250738585072E-308

Does not reproduce on a mac, confirmed:

mac:junk yuval$ cat p.php 
<?php
echo "a";
$d = 2.2250738585072011e-308; 
echo "b\n";
mac:junk yuval$ php p.php 
ab
mac:junk yuval$ php -v
PHP 5.3.3 (cli) (built: Aug 22 2010 19:41:55) 
Copyright (c) 1997-2010 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies

It hangs on Debian:


aquilax@zelda /tmp> php -v
PHP Warning:  PHP Startup: Unable to load dynamic library 
'/usr/lib/php5/20090626+lfs/adodb.so' - /usr/lib/php5/20090626+lfs/adodb.so: 
cannot open shared object file: No such file or directory in Unknown on line 0
PHP 5.3.3-6 with Suhosin-Patch (cli) (built: Dec  7 2010 18:23:49) 
Copyright (c) 1997-2009 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies
    with Xdebug v2.1.0, Copyright (c) 2002-2010, by Derick Rethans
    with Suhosin v0.9.32.1, Copyright (c) 2007-2010, by SektionEins GmbH
aquilax@zelda /tmp> cat t.php 
<?php $d = 2.2250738585072011e-308; ?>
aquilax@zelda /tmp> time php t.php 
PHP Warning:  PHP Startup: Unable to load dynamic library 
'/usr/lib/php5/20090626+lfs/adodb.so' - /usr/lib/php5/20090626+lfs/adodb.so: 
cannot open shared object file: No such file or directory in Unknown on line 0
^CCommand terminated by signal 2
7.55user 0.02system 0:07.61elapsed 99%CPU (0avgtext+0avgdata 36720maxresident)k
0inputs+0outputs (0major+2620minor)pagefaults 0swaps

Check out the strace:

  lstat64("/home/ubuntu/junk/p.php", {st_mode=S_IFREG|0644, st_size=59, ...}) = 0
  lstat64("/home/ubuntu/junk", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
  lstat64("/home/ubuntu", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
  lstat64("/home", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
  ioctl(3, SNDCTL_TMR_TIMEBASE or TCGETS, 0xbfe51238) = -1  ENOTTY (Inappropriate ioctl for device)
  fstat64(3, {st_mode=S_IFREG|0644, st_size=59, ...}) = 0
  mmap2(NULL, 68, PROT_READ, MAP_PRIVATE, 3, 0) = 0xb78d1000

and then it hangs...

This only seems to affect 32-bit systems.

looking like a gcc optimizer bug, -O0 is fine where -O2 hangs

How about -O2 -ffloat-store ?

Happens here too 64bit CPU 32bit builds (win or linux)

Appears to hang when compiled for 32bit Intel code, but not 64bit code.

Hangs in zend_strtod() according to gdb.

Excellent analysis at http://news.ycombinator.com/item?id=2066084

I have the same problem on PHP 5.3.2 on 32-bit Linux.

Configure:

'./configure' '--with-apxs2=/usr/local/apache2/bin/apxs' '--with-
mssql=/usr/local/freetds' '--with-ldap' '--prefix=/usr/local/php5' '--with-
config-file-path=/usr/local/php5/etc' '--enable-sockets' '--enable-soap' '--
with-openssl' '--with-unixODBC=/usr' '--with-gd' '--with-jpeg-dir=/usr/lib' '--
with-pdo-odbc=unixODBC,/usr' '--with-pdo-dblib=/usr/local/freetds'


uname -a:

Linux servername 2.6.16.60-0.42.5-default #1 Mon Aug 24 09:41:41 UTC 2009 i686 
i686 i386 GNU/Linux

Update:  PHP 5.2.6 is NOT affected by this bug on the same 32-bit architecture as 
my previous post.

Same problem on 2 systems (hangs with CPU pegged at 100%).

I have two CentOS 5.5 systems running i386 PHP packages:
PHP 5.3.2 (cli) (built: Mar  4 2010 21:52:46), Zend Engine v2.3.0, with eAccelerator v0.9.6
CPU: 
processor       : 0 (and 1)
vendor_id       : GenuineIntel
cpu family      : 6
model           : 15
model name      : Intel(R) Core(TM)2 CPU          6420  @ 2.13GHz
stepping        : 6
cpu MHz         : 800.000
cache size      : 4096 KB
physical id     : 0
siblings        : 2
core id         : 0
cpu cores       : 2
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 10
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc pni mon itor ds_cpl vmx est tm2 cx16 xtpr lahf_lm
bogomips        : 2139.82

AND

PHP 5.3.3 (cli) (built: Jul 22 2010 16:41:20), Zend Engine v2.3.0, with eAccelerator v0.9.6

CPU:
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 15
model           : 2
model name      : Intel(R) Pentium(R) 4 CPU 2.00GHz
stepping        : 4
cpu MHz         : 1993.668
cache size      : 512 KB
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 2
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm up
bogomips        : 3987.33

Package's build settings:
./configure --build=i686-redhat-linux-gnu --host=i686-redhat-linux-gnu --target=i386-redhat-linux-gnu --program-prefix= --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib --libexecdir=/usr/libexec --localstatedir=/var --sharedstatedir=/usr/com --mandir=/usr/share/man --infodir=/usr/share/info --cache-file=../config.cache --with-libdir=lib --with-config-file-path=/etc --with-config-file-scan-dir=/etc/php.d --disable-debug --with-pic --disable-rpath --without-pear --with-bz2 --with-exec-dir=/usr/bin --with-freetype-dir=/usr --with-png-dir=/usr --with-xpm-dir=/usr --enable-gd-native-ttf --with-t1lib=/usr --without-gdbm --with-gettext --with-gmp --with-iconv --with-jpeg-dir=/usr --with-openssl --with-zlib --with-layout=GNU --enable-exif --enable-ftp --enable-magic-quotes --enable-sockets --enable-sysvsem --enable-sysvshm --enable-sysvmsg --with-kerberos --enable-ucd-snmp-hack --enable-shmop --enable-calendar --with-libxml-dir=/usr --enable-xml --with-system-tzdata --with-apxs2=/usr/sbin/apxs --enable-maintainer-zts --with-config-file-scan-dir=/etc/php-zts.d --enable-force-cgi-redirect --enable-pcntl --with-imap=shared --with-imap-ssl --enable-mbstring=shared --enable-mbregex --with-gd=shared --enable-bcmath=shared --enable-dba=shared --with-db4=/usr --with-xmlrpc=shared --with-ldap=shared --with-ldap-sasl --with-mysql=shared,mysqlnd --with-mysqli=shared,mysqlnd --enable-mysqlnd-threading --with-oci8=shared,instantclient,/usr/lib/oracle/11.1.0.7/client/lib,11.1.0.7 --with-pdo-oci=shared,instantclient,/usr,11.1.0.7 --with-interbase=shared,/usr/lib/firebird --with-pdo-firebird=shared,/usr/lib/firebird --enable-dom=shared --with-pgsql=shared --enable-wddx=shared --with-snmp=shared,/usr --enable-soap=shared --with-xsl=shared,/usr --enable-xmlreader=shared --enable-xmlwriter=shared --with-curl=shared,/usr --enable-fastcgi --enable-pdo=shared --with-pdo-odbc=shared,unixODBC,/usr --with-pdo-mysql=shared,mysqlnd --with-pdo-pgsql=shared,/usr --with-pdo-sqlite=shared,/usr --with-pdo-dblib=shared,/usr --without-sqlite3 --with-sqlite=shared,/usr --enable-json=shared --enable-zip=shared --without-readline --with-libedit --with-pspell=shared --enable-phar=shared --with-mcrypt=shared,/usr --with-tidy=shared,/usr --with-mssql=shared,/usr --enable-sysvmsg=shared --enable-sysvshm=shared --enable-sysvsem=shared --enable-posix=shared --with-unixODBC=shared,/usr --enable-fileinfo=shared --enable-intl=shared --with-icu-dir=/usr --with-enchant=shared,/usr --with-recode=shared,/usr

See

http://www.exploringbinary.com/php-hangs-on-numeric-value-2-2250738585072011e-308/
http://www.reddit.com/r/programming/comments/evtrq/php_hangs_on_numeric_value_22250738585072011e308/
http://news.ycombinator.com/item?id=2066084

for lots of additional comments on this issue.

This is an interesting bug.  How about we just mark these as volatile doubles in 
that part of the code to make sure they don't end up in registers.  My guess is 
that it would fix it.  Need to track down a 32-bit machine to test this though.

Same happens on my Ubuntu box as well.

$ php -v
PHP 5.3.3-1ubuntu9.1 with Suhosin-Patch (cli) (built: Oct 15 2010 14:17:04)
Copyright (c) 1997-2009 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies


$ uname -a
Linux Server2 2.6.35-23-generic-pae #41-Ubuntu SMP Wed Nov 24 10:35:46 UTC 2010 
i686 GNU/Linux

[christandiono@hang1 ~]$ uname -a
FreeBSD hang1 8.0-RELEASE-p3 FreeBSD 8.0-RELEASE-p3 #0: Wed May 26 05:45:12 UTC 
2010     root@i386-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC  i386
[christandiono@hang1 ~]$ php -v
PHP 5.3.4 with Suhosin-Patch (cli) (built: Dec 20 2010 18:00:57) 
Copyright (c) 1997-2009 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies

[chris@hang2 ~]$ uname -a
Linux hang2 2.6.36-ARCH #1 SMP PREEMPT Wed Nov 24 06:44:11 UTC 2010 i686 
Intel(R) Core(TM) Duo CPU T2400 @ 1.83GHz GenuineIntel GNU/Linux
[chris@hang2 ~]$ php -v
PHP 5.3.4 with Suhosin-Patch (cli) (built: Dec 16 2010 21:19:01) 
Copyright (c) 1997-2009 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies

[chris@nohang ~]$ uname -a
Darwin nohang 10.5.0 Darwin Kernel Version 10.5.0: Fri Nov  5 23:20:39 PDT 2010; 
root:xnu-1504.9.17~1/RELEASE_I386 i386 i386
[chris@nohang ~]$ php -v
PHP 5.3.3 (cli) (built: Aug 22 2010 19:41:57) 
Copyright (c) 1997-2010 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies

Hangs on FreeBSD and Linux, not on Mac OS X. It might be worth noting that the 
last two machines have the same CPU (the Linux and Mac OS X machines).

Does not reproduce on php 5.3.4 (with gentoo patches, compiled -O2).

driana@undine ~/h $ cat numericval.php
<?php $d = 2.2250738585072011e-308; echo $d + 0; echo "\n"; ?>

driana@undine ~/h $ php numericval.php
2.2250738585072E-308

driana@undine ~/h $ php -v
PHP 5.3.4-pl0-gentoo (cli) (built: Dec 24 2010 14:24:29)
Copyright (c) 1997-2010 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies

driana@undine ~/h $ uname -a
Linux undine 2.6.28-hardened-r9-hrd-undine #1 SMP Thu Nov 12 02:29:42 CET 2009 i686 Intel(R) Pentium(R) Dual CPU E2180 @ 2.00GHz GenuineIntel GNU/Linux

Configure Command =>  './configure'  '--prefix=/usr' '--build=i686-pc-linux-gnu' '--host=i686-pc-linux-gnu' '--mandir=/usr/share/man' '--infodir=/usr/share/info' '--datadir=/usr/share' '--sysconfdir=/etc' '--localstatedir=/var/lib' '--prefix=/usr/lib/php5.3' '--mandir=/usr/lib/php5.3/man' '--infodir=/usr/lib/php5.3/info' '--libdir=/usr/lib/php5.3/lib' '--with-libdir=lib' '--without-pear' '--enable-maintainer-zts' '--disable-bcmath' '--with-bz2' '--disable-calendar' '--with-curl' '--without-curlwrappers' '--without-enchant' '--enable-exif' '--enable-ftp' '--with-gettext' '--without-gmp' '--disable-intl' '--without-kerberos' '--enable-mbstring' '--with-mcrypt' '--without-mssql' '--with-onig=/usr' '--with-openssl' '--with-openssl-dir=/usr' '--enable-pcntl' '--with-pgsql' '--without-pspell' '--without-recode' '--disable-shmop' '--without-snmp' '--disable-soap' '--disable-sockets' '--without-sybase-ct' '--disable-sysvmsg' '--disable-sysvsem' '--disable-sysvshm' '--with-tidy' '--disable-wddx' '--with-xmlrpc' '--without-xsl' '--enable-zip' '--with-zlib' '--disable-debug' '--enable-dba' '--without-cdb' '--without-db4' '--disable-flatfile' '--with-gdbm' '--disable-inifile' '--without-qdbm' '--with-freetype-dir=/usr' '--with-t1lib=/usr' '--enable-gd-jis-conv' '--with-jpeg-dir=/usr' '--with-png-dir=/usr' '--without-xpm-dir' '--with-gd' '--with-imap' '--with-imap-ssl' '--without-interbase' '--with-mysql=/usr' '--with-mysql-sock=/var/run/mysqld/mysqld.sock' '--with-mysqli=/usr/bin/mysql_config' '--without-oci8' '--without-pdo-dblib' '--with-pdo-mysql=/usr' '--with-pdo-pgsql' '--with-pdo-sqlite=/usr' '--without-pdo-odbc' '--with-readline' '--without-libedit' '--without-mm' '--with-sqlite=/usr' '--enable-sqlite-utf8' '--with-pic' '--with-pcre-regex=/usr' '--with-pcre-dir=/usr' '--with-config-file-path=/etc/php/cli-php5.3' '--with-config-file-scan-dir=/etc/php/cli-php5.3/ext-active' '--enable-cli' '--disable-cgi' '--disable-fpm' '--disable-embed' '--without-apxs2'

CFLAGS="-march=core2 -mfpmath=sse -O2 -pipe -fforce-addr -fomit-frame-pointer"

Re: last comment, I believe "-mfpmath=sse" did the trick. apologies for cluttering the bug report.

Guys, we already know the problem.  We are hitting an annoying x87 FPU design 
flaw.  You can read all about it here if you are interested:

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=323

And there is a good paper on it here:

http://hal.archives-ouvertes.fr/docs/00/28/14/29/PDF/floating-point-article.pdf

We don't need any more compile reports.  If you are on an architecture that uses 
the x87 FPU and you haven't forced SSE or float-store then you will see this 
problem.

PHP 5.2.6-1+lenny9 with Suhosin-Patch 0.9.6.2 (cli) (built: Aug  4 2010 03:25:57)
Copyright (c) 1997-2008 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2008 Zend Technologies

The bug is NOT present in this version.

This bug has been fixed in SVN.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.
 
Thank you for the report, and for helping us make PHP better.

Taking the hand, another bug (crash) happens here. Will post bt&co as soon as possible.

My bad, forgot to revert a change in my previous attempt to fix this issue. Fresh co & build works, tests pass.

Seems that the commit did not make it here:

Fix: http://svn.php.net/viewvc?view=revision&revision=307095
Test case: http://svn.php.net/viewvc?view=revision&revision=307097

I have this problem on PHP-5.2.14 on Windows XP SP3
C:\Documents and Settings\user>php -v
PHP 5.2.14 (cli) (built: Jul 21 2010 18:43:55)
Copyright (c) 1997-2010 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2010 Zend Technologies

Just for the record, because some of my friends missed this:
max_execution_time/set_time_limit cannot help you with this problem, because it's only gets checked between two userland instructions, hence this won't happen in 
this case.

Tyrael

btw. 5.2 support officially ended.
are there any chances that this bug will be fixed in 5.2, or this will be the 
first obstacle which will force the people out there to upgrade to 5.3?

Tyrael

@Tyrael: Seems like it was already fixed for 5.2.
http://svn.php.net/viewvc/php/php-src/branches/PHP_5_2/Zend/zend_strtod.c?
view=log&pathrev=307095

Considering the official Windows binaries are affected by this, will there be new binaries or a new PHP version released to reflect this issue?

I'm asking because it is possible to take down vulnerable PHP apps by this as easily as finding a request variable that is actually accessed. Requesting viewtopic.php?f=2.2250738585072011e-308 for phpBB or index.php?q=2.2250738585072011e-308 for Drupal is enough to freeze the PHP installation if it is affected.

@ cswarth at gmail dot com 

Thanks for all the feedbacks, we had enough info and details to fix the issue and 
new releases will be done shortly.

As a workaround until I can patch php I have used the following pure php solution:

http://stackoverflow.com/questions/4610651/any-problems-with-the-following-work-
around-for-php-bug-53632

hang on mine. 32 bit

gangzheng@CDPL-PC-08:~$ php -v
PHP 5.3.3-1ubuntu9.1 with Suhosin-Patch (cli) (built: Oct 15 2010 14:17:04) 
Copyright (c) 1997-2009 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies
gangzheng@CDPL-PC-08:~$ uname -a
Linux CDPL-PC-08 2.6.35-24-generic #42-Ubuntu SMP Thu Dec 2 01:41:57 UTC 2010 i686 GNU/Linux

My script:
# cat bug.php 
<?php 
$d = 2.2250738585072011e-308; 
?>

Result: NO HANG.
Php version:
# php -v
PHP 5.1.6 (cli) (built: Nov 29 2010 16:47:37) 
Copyright (c) 1997-2006 The PHP Group
Zend Engine v2.1.0, Copyright (c) 1998-2006 Zend Technologies

OS: CentOS 5.4 32-bit
Kernel: 2.6.18-164.el5xen
CPU:
# cat /proc/cpuinfo 
processor	: 0
vendor_id	: GenuineIntel
cpu family	: 15
model		: 4
model name	: Intel(R) Pentium(R) 4 CPU 3.00GHz
stepping	: 3
cpu MHz		: 3000.084
cache size	: 2048 KB
fdiv_bug	: no
hlt_bug		: no
f00f_bug	: no
coma_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 5
wp		: yes
flags		: fpu de tsc msr pae cx8 apic cmov pat clflush acpi mmx fxsr sse sse2 ss ht nx constant_tsc up pni cid
bogomips	: 7505.37

ok, let block the comments here for now. Bug has been identified, releases on 
their way. Thanks everyone for your feedback.

Reopen, assign to me, VC6 5.2 does not work as it should everywhere.

VC6 builds are now fixed. 5.2.17 and 5.3.5 have been retaged. windows.php.net has the updated binaries. SVN php web distributions contain 5.2.17 updated binaries as well but be sure that you get the right one (md5 or use windows.php.net) if you rely on a mirror.

Thank you for your bug report. This issue has already been fixed
in the latest released version of PHP, which you can download at 
http://www.php.net/downloads.php