gdb: M2 Defaults

 
 15.4.9.5 Modula-2 Defaults
 ..........................
 
 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.  SeeHaving GDB Infer the Source Language
 Automatically, for further details.