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Never rebuild diagnostic


Select the diagnostic action that Simulink® software should take if it detects a model reference target that needs to be rebuilt.

Category: Model Referencing


Default: Error if rebuild required


Simulink takes no action.

Warn if rebuild required

Simulink displays a warning.

Error if rebuild required

Simulink terminates the simulation and displays an error message.


If you set the Rebuild parameter to Never and set the Never rebuild diagnostic parameter to Error if rebuild required or Warn if rebuild required, then Simulink:

  • Performs the same change detection processing as for the If any changes in known dependencies detected rebuild option setting, except it does not compare structural checksums

  • Issues an error or warning (depending on the Never rebuild diagnostic setting), if it detects a change

  • Never rebuilds the model reference target

Selecting None bypasses dependency checking, and thus enables faster updating, simulation, and code generation. However, the None setting can cause models that are not up to date to malfunction or generate incorrect results. For more information on the dependency checking, see Rebuild.


This parameter is enabled only if you select Never in the Rebuild field.

Command-Line Information

Parameter: CheckModelReferenceTargetMessage
Value: 'none' | 'warning' | 'error'
Default: 'error'

Recommended Settings

DebuggingNo impact
TraceabilityNo impact
EfficiencyNo impact
Safety precautionError if rebuild required

See Also


Model Settings

Related Topics