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Subject: broken shutdown for dl()'d modules (HEAD)
From: wez@thebrainroom.com (Wez Furlong)

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Just noticed some segfaults during shutdown of dl()'d modules from the 
CLI; this is what I see running under valgrind:

==19025== discard syms in 
/usr/local/php5/lib/php/extensions/no-debug-non-zts-20040718/pdo_sqlite.so 
due to munmap()
==19025== discard syms in /usr/local/lib/libsqlite3.so.0.8.6 due to munmap()
==19025== discard syms in 
/usr/local/php5/lib/php/extensions/no-debug-non-zts-20040718/pdo.so due 
to munmap()
==19025== Invalid read of size 4
==19025==    at 0x8184ABC: _zval_dtor (zend_variables.c:55)
==19025==    by 0x817C2E0: _zval_ptr_dtor (zend_execute_API.c:393)
==19025==    by 0x818BE8B: zend_hash_apply_deleter (zend_hash.c:574)
==19025==    by 0x818BF19: zend_hash_graceful_reverse_destroy 
(zend_hash.c:640)
==19025==    Address 0x4239AA24 is not stack'd, malloc'd or free'd
zsh: 19025 segmentation fault  valgrind /usr/local/php5/bin/php ./sqlite.php

This looks to be our old friend 
Mr.-access-pointers-and-functions-after-we-dlclosed-the-module.  Sure 
enough, removing the dlclose() call fixes the segfault.

This smells like a shutdown order problem; the script creates two 
objects, and if I unset them before the script end there is no segfault.

--Wez.

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Index: Zend/zend_API.c
===================================================================
RCS file: /repository/ZendEngine2/zend_API.c,v
retrieving revision 1.262
diff -u -p -r1.262 zend_API.c
--- Zend/zend_API.c	9 Sep 2004 16:51:45 -0000	1.262
+++ Zend/zend_API.c	19 Sep 2004 10:08:17 -0000
@@ -1497,7 +1497,7 @@ void module_destructor(zend_module_entry
 		zend_unregister_functions(module->functions, -1, NULL TSRMLS_CC);
 	}
 
-#if HAVE_LIBDL
+#if HAVE_LIBDL && 0
 	if (module->handle) {
 		dlclose(module->handle);
 	}

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