Re: Fortran and .NET (C#)

Richard E Maine wrote:
Let me repeat for the second time (at least) in this thread, and not counting many times in previous thready. You *CANNOT* leak memory because of a user error with Fortran allocatable arrays. That is an intentional part of the design of Fortran allocatables. It is so much a part of the design, that if you managed to find a way to do it, I am confident that it would be regarded as a bug in the standard and a fix would be published. In the many times I have explained this, not once has anyone come up with a code sample to contradict it.

It occurs to me that one could perhaps argue that Fortran allocatable arrays use a simplistic form of reference-counting garbage collection that can be implemented with zero cost at compile time. Namely, the language does not permit more than one "pointer" (by which I mean allocatable array variable, not a real pointer) to refer to a given piece of memory allocated as an allocatable array, and therefore, when a "pointer" is dereferenced (by going out of scope, or whatever), the compiler can assume the reference count has gone to zero and thus deallocate the memory.

I doubt that this is a helpful way of looking at things, however.

- Brooks


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Relevant Pages

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