Re: [Gnu-arch-users] 64-bit cleaning [PATCH]

[John Goerzen]

On Mon, Sep 08, 2003 at 03:30:03PM +0900, Stephen J. Turnbull wrote:
> >>>>> "John" == John Goerzen <address@hidden> writes:
> 
>     John> (-Wall is very useful on gcc)
> 
> Either -Wstrict-aliasing or -fno-strict-aliasing is a really good
> idea.  (AFAIK gcc 3.x doesn't warn on aliasing with -Wall, but it
> really should.)  Arch in particular is known to have a few places with
> aliasing issues.

My understanding of those options (I assume you meant -fstrict-aliasing) is
somewhat limited, but from the manpage, it indicates:

          vates optimizations based on the type of expressions.  In particu-
           lar, an object of one type is assumed never to reside at the same
           address as an object of a different type, unless the types are
           almost the same.  For example, an "unsigned int" can alias an
           "int", but not a "void*" or a "double".  A character type may alias
           any other type.

Given that hackerlab does exactly that all over the place, it would require
conversion of a lot of code to use unions instead of void *.

I'm not opposed to that, and personally think it a good idea, but I'd rather
not do it until Tom indicates he'd accept such changes.  Tom?

-- John