Array Bounds

Why didn't Fortran tell us when we accessed beyond the bounds of the array in the subroutine? Think about this carefully.

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Can you design an experiment to determine whether Fortran will do array bounds checking within a subroutine, just as it does in the main program?

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What happens now when we run the program?

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So here's our problem in a nutshell:

• This version of Fortran does indeed warn us when we access outside the declared bounds of an array in a subroutine or a function.

• However, Fortran does not require that the declared bounds of a dummy array (in a subroutine or function) be the same as the declared bounds of the actual array (that appears in the function or subroutine call). (The checking program will, however, give us appropriate warnings.)

We can now see that our problem is to arrange that the declared bounds of all dummy and actual arrays be exactly the same. Unfortunately, this is impossible to do if we continue to use the approach embodied in ``aparm2.f''. Why is that?

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