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    1  MODULE MBadMVar;
    2  MODULE M EXPORT cnt, Bump;
    3  VAR cnt : INTEGER;
    4  PROCEDURE Bump(VAR x : INTEGER);
    5  BEGIN
    6    x := x + 1
    7  END Bump;
    8  END M;
    9  VAR ExitCode : INTEGER;
   10  BEGIN
   11    M.Bump(M.cnt);
*****             ^ invalid procedure call
   12    ExitCode := 0
   13  END MBadMVar.

    1 error