Description:
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pg_copy_to($db, 'x', "\t", NULL) causes SIGSEGV

NULL should be default values ???

Reproduce code:
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$db = pg_connect('host=localhost dbname=template1 user=postgres');

pg_copy_to($db, 'x', "\t", NULL);

Expected result:
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should be rewrited to pg_copy_to($db, 'x', "\t", '\N');

read data from table

Actual result:
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Starting program: /usr/local/php/bin/php -f x.php

Program received signal SIGSEGV, Segmentation fault.
0x08196665 in _efree (ptr=0x82b6564) at /root/src/php-5.0.5/Zend/zend_alloc.c:282
282             REMOVE_POINTER_FROM_LIST(p);
(gdb) bt
#0  0x08196665 in _efree (ptr=0x82b6564) at /root/src/php-5.0.5/Zend/zend_alloc.c:282
#1  0x080f4b42 in zif_pg_copy_to (ht=4, return_value=0x83c8e44, this_ptr=0x0, return_value_used=0) at /root/src/php-5.0.5/ext/pgsql/pgsql.c:2674
#2  0x081cad32 in zend_do_fcall_common_helper (execute_data=0xbfffd974, opline=0x83c325c, op_array=0x83bedc4) at /root/src/php-5.0.5/Zend/zend_execute.c:2760
#3  0x081d8c57 in zend_do_fcall_handler (execute_data=0xbfffd974, opline=0x83c325c, op_array=0x83bedc4) at /root/src/php-5.0.5/Zend/zend_execute.c:2894
#4  0x081c8662 in execute (op_array=0x83bedc4) at /root/src/php-5.0.5/Zend/zend_execute.c:1437
#5  0x081aab93 in zend_execute_scripts (type=8, retval=Variable "retval" is not available.
) at /root/src/php-5.0.5/Zend/zend.c:1064
#6  0x08175ecb in php_execute_script (primary_file=0xbffffd10) at /root/src/php-5.0.5/main/main.c:1643
#7  0x081df4aa in main (argc=3, argv=0xbffffdc4) at /root/src/php-5.0.5/sapi/cli/php_cli.c:946