Re: type based aliasing again

[craig@jcb-sc.com]

>The problem is that the anti-aliasing rules are an especially
>difficult and tricky part of the standard. If we demand that
>users know these rules that's akin to mandating having a copy of
>the standard. While helping people to learn is good, this is more
>like imposing difficulties on those that don't want to know.

There are two dominant solutions: 1) Change the standard; 2) Don't
program in C.  *Way* less appropriate than those is 3) Invent dialectal
behaviors and implement them to work around what programmers are
already supposed to know, which is what is being proposed here --
especially when those dialectal behaviors are triggered without the
use of *any* constructs that are clearly syntactically *invalid*
in the standard language.

In short, if people "don't want to know", they shouldn't be let
near a C compiler.  Remember all those pundits who claimed C was
inferior, for regular programmers, to some languages like FORTRAN 77,
because it imposed pointers on them?  This is where you're all supposed
to say "hey, they were right, these pointer thangs are *darn* complicated".

(My off-the-cuff opinion?  C programmers can't handle pointers *combined*
with Fortran-style aliasing prohibitions.  ISO C should have just
mandated straight-ahead, nearly-Java-like behavior for code, and
left optimization to the under-the-hood people.  I'm saying I actually
favor option #1 above.  If we leave things as they are in GCC, we
actually *promote* such a change better than if we cleverly try
to "accommodate" via option 3, and probably even better than if we
emit a nice warning.)

        tq vm, (burley)