🚀 go-pugleaf

Concerning some fancy pointer referencing stuff, michael@crlt.UUCP asks :

>I have heard that this is used in a number of kernels, and of course it
>would work in a lot of compiler-generated code that didn't do tricks with
>registers or storage allocation, and didn't waste a lot of processor and
>programmer effort trying to "protect" you against your folly, but where
>do K&R come out and say it is legal?  I just re-read the source I think
>would be the most likely place (the "pointers" chapter of the sky-blue
>C book) and didn't find it.

In section 14.1 of the K&R C Reference manual (Structures and Unions)
we find the loophole. In a reference to a structure, you are 
supposed to reference of of that structures components; but
"to allow an escape from the typing rules" (or perhaps to simplify
writing the early C compilers?) the restriction is not enforced.

The section is concluded with "Such constructions are non-portable.",
which pretty much summarizes it.  The compiler writer may take
poetic license with such strange constructs.

Roger Kaiser
uiucdcsp!kaiser