fallback to assembly when source code is not available

Author: eronnen

lldb/tools/lldb-dap/JSONUtils.cpp

@@ -750,9 +750,10 @@ llvm::json::Value CreateStackFrame(lldb::SBFrame &frame,
   EmplaceSafeString(object, "name", frame_name);
 
   auto line_entry = frame.GetLineEntry();
+  auto file_spec = line_entry.GetFileSpec();
   // A line entry of 0 indicates the line is compiler generated i.e. no source
   // file is associated with the frame.
-  if (line_entry.GetFileSpec().IsValid() &&
+  if (file_spec.IsValid() && file_spec.Exists() &&
       (line_entry.GetLine() != 0 ||
        line_entry.GetLine() != LLDB_INVALID_LINE_NUMBER)) {
     object.try_emplace("source", CreateSource(line_entry));