#36208 [Opn->WFx]: Symbols in libphp5.so conflict with symbols in libgd.so and cause apache probs

ID: 36208 Updated by: edink@php.net Reported By: hb at gentoo dot x256 dot org -Status: Open +Status: Wont fix Bug Type: Dynamic loading Operating System: Gentoo Linux x86 PHP Version: 5.1.2 New Comment: In case when you need to compile another apache module that uses gdlib you need to compile php with the system library. (--with-gd=/path/to/system/gdlib) Previous Comments: ------------------------------------------------------------------------ [2006-01-30 12:45:16] hb at gentoo dot x256 dot org Description: ------------ PHP includes a tweaked GD library. It is not compatible with libgd. The problem is, it uses the same symbols (i.e. function names) as libgd and exports them from its shared object. When I load mod_php and mod_perl into Apache, mod_perl programs using the GD library end up sometimes calling PHP's modified GD routines and sometimes not. This causes Apache children to crash semi-randomly. Since the PHP GD library is not compatible with libgd itself (and because it's likely to be co-existing with a different version of libgd on the system, regardless of tweaks), the symbols (functions and others) should be renamed. Perhaps with a PHP_ prefix. This way there will be no dynamic loading collision and PHP/PERL will be able to co-exist in Apache children without damage. I worked around this by recompiling libPHP with external GD library support. However, it took me several hours to diagnose the exact problem. I have also been bitten by this once before already. I recommend fixing this in PHP4 as well as PHP5. Reproduce code: --------------- This PERL/MASON script crashes every time if libphp5.so is loaded as an Apache module, but works perfectly otherwise: <%INIT> use strict; use GD::Graph::lines; my $tgraph = GD::Graph::lines->new(800, 800); my $tgd = $tgraph->plot([ [ "a" ], [ 0 ] ]); print $tgd->png(); return; </%INIT> Expected result: ---------------- Blank graph. Actual result: -------------- Zero-sized reply. GLIBC memory corruption reported upon free() in error_log. ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=36208&edit=1