<?php
function foo()
{
  debug_print_backtrace();
}
foo();
?>

After running the above script, the memory manager reports following leaks:

/home/koizumi/src/php.net/HEAD/php4/Zend/zend_hash.c(178) :  Freeing 0x0827FD54
(32 bytes), script=/tmp/test3.php
/home/koizumi/src/php.net/HEAD/php4/Zend/zend_builtin_functions.c(1166) :  Freei
ng 0x0827FCF4 (44 bytes), script=/tmp/test3.php
/home/koizumi/src/php.net/HEAD/php4/Zend/zend_API.c(565) : Actual location (loca
tion was relayed)
/home/koizumi/src/php.net/HEAD/php4/Zend/zend_builtin_functions.c(1165) :  Freei
ng 0x0827DD2C (12 bytes), script=/tmp/test3.php


Suggested patch (I'm going to resend this later):

Index: Zend/zend_builtin_functions.c
===================================================================
RCS file: /repository/Zend/zend_builtin_functions.c,v
retrieving revision 1.132
diff -u -r1.132 zend_builtin_functions.c
--- Zend/zend_builtin_functions.c       31 Dec 2002 15:55:01 -0000      1.132
+++ Zend/zend_builtin_functions.c       31 Dec 2002 20:53:31 -0000
@@ -1310,7 +1310,7 @@
                }
                zend_printf("%s(", function_name?function_name:"main");
                debug_print_backtrace_args(arg_array);
-               ZVAL_DELREF(arg_array);
+               zval_ptr_dtor(&arg_array);
                zend_printf(") called at [%s:%d]\n", filename, lineno);
                include_filename = filename;
                ptr = ptr->prev_execute_data;