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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Least Dangerous Way to Do This ?
Date: Mon, 15 Oct 2018 15:36:25 -0500
Organization: JSA Research & Innovation
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<patrick@spellingbeewinnars.org> wrote in message 
news:beac86f1-fa15-4719-bfc3-8d0334260906@googlegroups.com...
> Hi Everyone
>
> Okay, don't laugh(or laugh too hard)
>
> I need to interface with automatically generated C. function pointers are 
> represented as a pointer to a pointer to a char. This is weird but done 
> for pointer arithmetic purposes.

It's not certain (in the real world, at least) if a function pointer and an 
object pointer have the same representation. We treat them as completely 
different things in our code generator, because some weird machines (in 
particular the U2200) have very large representations for function pointers 
(one version was 8 36-bit words!). Similarly, on the 16-bit 8086 compilers, 
function pointers carried a segment (thus a 32-bit address), and object 
pointers usually didn't (thus a 16-bit address).

So if you want this code to work in different environments, I'd try to avoid 
mixing the two (as Simon suggested).

                                                  Randy.