gcc builtin atomic functions are sometimes used when they are not available

[2010-08-28 22:37 UTC] fedora at famillecollet dot com

Description:
------------
Build fails on RHEL/Centos 5 (gcc-4.1.2)

sapi/fpm/fpm/fpm_shm_slots.o: In function `fpm_spinlock':
/builddir/build/BUILD/php5.3-201008281230/sapi/fpm/fpm/fpm_atomic.h:148: undefined reference to `__sync_bool_compare_and_swap_4'
/builddir/build/BUILD/php5.3-201008281230/sapi/fpm/fpm/fpm_atomic.h:143: undefined reference to `__sync_bool_compare_and_swap_4'

This seems linked to commit 302600
http://svn.php.net/viewvc/php/php-src/branches/PHP_5_3/sapi/fpm/fpm/fpm_atomic.h?r1=299794&r2=302600

Changing the test fixes the issue  
#if (__GNUC__) && (__GNUC__ >= 4 &&  __GNUC_MINOR__ >= 2)

I don't know which is the correct value.

Build ok on fedora 12 (gcc-4.4.4) and fedora 13 (gcc-4.4.4)

[2010-08-29 00:35 UTC] felipe@php.net

-Status: Open +Status: Assigned -Assigned To: +Assigned To: fat

[2010-08-30 15:47 UTC] fat@php.net

-Status: Assigned +Status: Feedback

[2010-08-30 15:47 UTC] fat@php.net

Not enough information was provided for us to be able
to handle this bug. Please re-read the instructions at
http://bugs.php.net/how-to-report.php

If you can provide more information, feel free to add it
to this bug and change the status back to "Open".

Thank you for your interest in PHP.


Can you please try the following patch ?

Don't forget to run ./buildconf before executing ./configure --enable-fpm && make.

Thanks

[2010-08-30 18:19 UTC] fedora at famillecollet dot com

-Status: Feedback +Status: Assigned

[2010-08-30 18:19 UTC] fedora at famillecollet dot com

Try build of latest snapshot (201008301430) with your patch

Fedora 13 x86_64 - gcc 4.4.4 : BUILD OK

$ grep HAVE_BUILTIN_ATOMIC build-fpm/main/php_config.h 
#define HAVE_BUILTIN_ATOMIC 1

Enterprise Linux 5 i386 - gcc 4.1.2 : BUILD OK

$ grep HAVE_BUILTIN_ATOMIC build-fpm/main/php_config.h
/* #undef HAVE_BUILTIN_ATOMIC */


So, the patch seems fine to me.
Thanks for taking care of this.

[2010-09-01 10:15 UTC] fat@php.net

-Summary: undefined reference to `__sync_bool_compare_and_swap_4' +Summary: gcc builtin atomic functions are sometimes used when they are not available -Status: Assigned +Status: Analyzed

[2010-09-01 10:18 UTC] fat@php.net

-Status: Analyzed +Status: Closed

[2010-09-01 10:18 UTC] fat@php.net

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.