🚀 go-pugleaf

In article <14330@ksr.com>, jfw@ksr.com (John F. Woods) writes:
|> 
|> >For example:
|> >	printf("%d\n", (offsetof(foo, y) - offset(foo, x)) - sizeof(int));
|> >should print 0 on any standards conforming compiler, if it is true that the
|> >standard permits only padding for the purpose of creating proper alignment.
|> 
|> Conversely, in the absense of any means of deriving from the Standard this
|> unstated requirement, the program is not strictly conforming.

Huh? The Standard and everything in it (e.g. definition of printf, offsetof, 
sizeof, int; and the statement about padding) together defines what that 
program must output, and by a literal interpretation, that program is SC.

|> 
|> The Rationale isn't the Standard, but I'll quote it anyway: 3.5.2.1 "Since
|> some existing implementations, in the interest of enhanced access time, leave
|> internal holes larger than absolutely necessary, it is not clear that a
|> portable deterministic method can be given for traversing a structure field
|> by field."

Oh! Well, that's a horse of a different color! Certainly, an interpretation
ruling that favored the Rationale's statement would override a literal
interpretation of the Standard. But I think such a ruling would be necessary.
It doesn't follow from "as-if".

-Chris
-- 
==================
Chris Volpe
G.E. Corporate R&D
volpecr@crd.ge.com