Modula-2 defaults
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   If type and range checking are set automatically by GDB, they both
default to `on' whenever the working language changes to Modula-2.
This happens regardless of whether you, or GDB, selected the working
language.

   If you allow GDB to set the language automatically, then entering
code compiled from a file whose name ends with `.mod' sets the working
language to Modula-2. See Having GDB set the language automatically: Automatically, for further details.