Suppress VitalGlitch Warnings in QuestaSim

Suppressing VitalGlitch Warnings in QuestaSim

The documented way to suppress VitalGlitch warnings is through the flags -noglitch or +no_glitch_msg as part of the vsim command. If you find that these flags are not working for you, please check the settings in QuestaSim below.

Ensure that "Optimize for: VITAL" is enabled

In the Compile > Compile Options... > VHDL tab of the QuestaSim GUI, ensure that the "Optimize for: VITAL" checkbox is selected in the compilation settings.

When this option is enabled:

• The VITAL timing processes are compiled at the kernel level.
• The simulation engine recognizes the -noglitch and +no_glitch_msg flags.
• The warnings are suppressed as expected.

This setting effectively modifies the modelsim.ini file by setting NoVital = 0. According to the QuestaSim documentation (page 1675), NoVital = 0 enables the acceleration of VITAL packages.

Re-run your simulation to observe the effect of the setting. The VitalGlitch suppression flags should successfully eliminate the warnings.

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