Help: call_user_function() core dumps

I am new to PHP extension writing and embedding. Following the book from Sara Goleman - Extending and Embedding PHP (Developer's Library) I wrote the following program based on her example in Chap. 20 =================================================================== #include <stdio.h> #include <stdlib.h> #include <sapi/embed/php_embed.h> int main(int argc, char** argv) {

     PHP_EMBED_START_BLOCK(argc, argv);

zval* args[2]; zval funcname; zval input_str; zval count; zval retval; char* ans;

     ZVAL_STRING(&funcname, "str_repeat", 0);

args[0] = &input_str; args[1] = &count; ZVAL_STRINGL(args[0], "DHIRU ", 6, 0); ZVAL_LONG(args[1], 5L);

     call_user_function(EG(function_table), NULL, &funcname, &retval, 2, args TSRMLS_CC);
     ans = Z_STRVAL(retval);

printf("%s\n", ans);

     PHP_EMBED_END_BLOCK();
     return 0;

} ======================================================================== When I run this program it core dumps with the following message: /export/home/dhiru/work/php/php-5.2.5/Zend/zend_variables.h(35) : Block 0x08049188 status: /export/home/dhiru/work/php/php-5.2.5/Zend/zend_variables.c(36) : Actual location (location was relayed) Invalid pointer: ((thread_id=0x4C45535F) != (expected=0xB78D26B0)) Segmentation fault (core dumped) When I step thru the debugger it appears that the function str_repeat call is successful via zend_call_function(), but after the call to the str_repeat function it tries to execute zend_ptr_stack_clear_multiple(TSRMLS_C), which in turn calls zend_mm_check_ptr() and something seems to go wrong here : #ifdef ZTS if (ZEND_MM_BAD_THREAD_ID(p)) {

       if (!silent) {
           zend_debug_alloc_output("Invalid pointer: ((thread_id=0x%0.8X) != (expected=0x%0.8X))\n", (long)p->thread_id, (long)tsrm_thread_id());
           had_problems = 1;
       } else {
           return zend_mm_check_ptr(heap, ptr, 0 ZEND_FILE_LINE_RELAY_CC ZEND_FILE_LINE_ORIG_RELAY_CC);
       }

} #endif Any help will be greatly appreciated Thanks, -Dhiru P.S.: I am using Ubuntu and PHP 5.2.5