Fix FLF backtrace

Signed-off-by: Bob Weinand <[email protected]>

ext/collect_backtrace.c

@@ -222,7 +222,7 @@ static inline zend_bool skip_internal_handler(zend_execute_data *skip) /* {{{ */
 /* Copy of zend_fetch_debug_backtrace with ability to gather local variables */
 void ddtrace_fetch_debug_backtrace(zval *return_value, int skip_last, int options, int limit)
 {
-    zend_execute_data *call;
+    zend_execute_data *call, *last_call = NULL;
     zend_object *object;
     bool fake_frame = 0;
     int lineno, frameno = 0;
@@ -274,6 +274,7 @@ void ddtrace_fetch_debug_backtrace(zval *return_value, int skip_last, int option
 
     if (skip_last) {
         /* skip debug_backtrace() */
+        last_call = call;
         call = call->prev_execute_data;
     }
 
@@ -334,6 +335,9 @@ void ddtrace_fetch_debug_backtrace(zval *return_value, int skip_last, int option
             stack_frame = zend_new_array(8);
             zend_hash_real_init_mixed(stack_frame);
             zend_function *func = ZEND_FLF_FUNC(opline);
+            if (last_call && last_call->func == func) {
+                goto not_frameless_call;
+            }
             zend_string *name = func->common.function_name;
             ZVAL_STRINGL(&tmp, ZSTR_VAL(name), ZSTR_LEN(name));
             _zend_hash_append_ex(stack_frame, ZSTR_KNOWN(ZEND_STR_FUNCTION), &tmp, 1);
@@ -566,6 +570,7 @@ void ddtrace_fetch_debug_backtrace(zval *return_value, int skip_last, int option
         } else {
             fake_frame = 0;
             include_filename = filename;
+            last_call = call;
             call = prev;
         }
     }