Fix PDOStatement::execute parameter error in specific scenarios

Array to string conversion occurs when the PDOStatement::execute parameter is empty in a specific scenario.

Author: longxinH

extension/php_xhprof.h

@@ -39,7 +39,7 @@ extern zend_module_entry xhprof_module_entry;
  */
 
 /* XHProf version                           */
-#define XHPROF_VERSION       "2.0.4"
+#define XHPROF_VERSION       "2.0.5"
 
 /* Fictitious function name to represent top of the call tree. The paranthesis
  * in the name is to ensure we don't conflict with user function names.  */

extension/xhprof.c

@@ -1501,6 +1501,11 @@ char* hp_trace_callback_pdo_statement_execute(char *symbol, zend_execute_data *d
         return result;
 #endif
 
+        if (ZEND_CALL_NUM_ARGS(data) < 1) {
+            spprintf(&result, 0, "%s#%s", symbol, Z_STRVAL_P(query_string));
+            return result;
+        }
+
         arg = ZEND_CALL_ARG(data, 1);
         if (Z_TYPE_P(arg) != IS_ARRAY) {
             spprintf(&result, 0, "%s#%s", symbol, Z_STRVAL_P(query_string));