LLDB "parent failed to evaluate: variable not available"

Hello! I am having some issues with the LLDB debugger. If I create an array of std::vector with a literal (e.g. vector<int> a[3]), I can freely view it in the debugger variables. However, if I specify the length with a variable (e.g. int n = 3; vector<int> a[n];), the debugger displays "parent failed to evaluate: variable not available" in the variables pane.

Do you have any advice on how to inspect these variables in debug mode? I've read this can be a consequence of code optimization, but I cannot figure out how to disable optimization in debug mode.

Thanks for the help!