diff --git a/pkg/proc/threads.go b/pkg/proc/threads.go
index b5c12df01d35490a08b456df8600878282ea9463..c18b6f8d8083a1c45a963a0f8d2325c655c9ce2f 100644
--- a/pkg/proc/threads.go
+++ b/pkg/proc/threads.go
@@ -112,7 +112,8 @@ func next(dbp Process, stepInto bool) error {
 		}
 	}()
 
-	csource := filepath.Ext(topframe.Current.File) != ".go"
+	ext := filepath.Ext(topframe.Current.File)
+	csource := ext != ".go" && ext != ".s"
 	var thread MemoryReadWriter = curthread
 	var regs Registers
 	if selg != nil && selg.Thread != nil {