Re: anyone interested in decompilation

Jürgen Kahrs wrote:


(snip regarding Java, JVM, pointers, and references)


> The Java type "reference" misses not only pointer arithmetic but also
> type casting (of pointers) and the address operator (&). You may of
> course argue that such features are not desirable. The absence of
> such feature makes it much harder to write compilers for a translation
> from ISO C to JVM.


Well, if a pointer variable includes a reference and offset, it
comes close to what is needed. Arithmetic operations only change
the offset, and the offset is used when the pointer is dereferenced.
(Note that C make no guarantee as to the result of comparison
other than equal/not equal for pointers to different objects.)


The & operator is different. As far as I know, you have to make
all scalar variables into arrays dimensioned one. Then they can
be referenced as arrays are. Another way is to allocate all
scalar variables of a given type as one array with different
offsets. That might be more C like!


I have, for example, used an array dimensioned one with a Hashtable,
and can then dereference it and increment it in one expression,
after having tested that the entry exists.


-- glen

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