MATLAB: Find reason for this warning msg: Variable ‘hws’ originally saved as a handle cannot be instantiated as an object and will be read in as a uint32.

MATLABmodel workspace

load_system('input_check')
hws = get_param('input_check', 'modelworkspace');
hws.DataSource = 'MAT-File';
hws.FileName = 'slx_input_check_pars.mat';
hws.reload; % Line 66 
% sim('input_check')
close_system('input_check')
I am loading some parameters to model workspace of Simulink model 'input_check', code is shown above, run the code get a warning msg as,
Warning: Variable 'hws' originally saved as a handle cannot be instantiated as an object and will be read in as a uint32.
> In run_idp (line 66)
line 66 is marked in the code, % Line 66
I am worried about whether this property woud cause error later so want to know what causes this warning. Isn't 'reload' a valid function?
https://www.mathworks.com/help/simulink/slref/simulink.modelworkspace.html
Another example from: https://www.mathworks.com/help/simulink/ug/change-model-workspace-data.html
hws = get_param(bdroot, 'modelworkspace');
hws.DataSource = 'MAT-File';
hws.FileName = 'params';
hws.assignin('pitch', -10);
hws.assignin('roll', 30);
hws.assignin('yaw', -2);
hws.saveToSource;
hws.assignin('roll', 35);
hws.reload;

Best Answer

My suspect is that there is a variable also called 'hws' in the .mat file. It was the handle of an object. For example, the handle of certain graphical object appear to be the value of an integer. It was saved to the .mat file by accident.
The object no longer exists. Thus, when you reload the .mat file to the model workspace. The error message appears.
Check the content of your .mat file. Attach it here if possible. Also indicate your MATLAB version.
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