Re: Arithmetic Shift

[Andrew W. Nosenko]

On Sat, Dec 11, 2010 at 05:39, Bob Friesenhahn
<address@hidden> wrote:
> On Fri, 10 Dec 2010, Andrew W. Nosenko wrote:
>>
>> Excuse me?  Why do you think that preprocessor should match the
>> behavior of compiler???
>
> Excuse me?  Why do you think that the behavior of the compiler should be
> consistent? :-)
>
>> Why, why system's /usr/bin/cpp that come from GCC should match to
>> Clang's behavior?  Or ICC's behavior?  Remember: Accordingly to your
>> logic, if it doesn't match, then it is invalid.  Why?  And if ICC and
>> Clang interpret -1 >> 1 differently, then it renders GCC's CPP
>> constantly invalid?
>
> Since you mention Clang (LLVM-based) then it is worth pointing out that
> final code generation may be delayed and so it is possible that the CPU type
> finally selected may not match the CPU type on which the original tests were
> executed.  Part of the behavior depends on the CPU.

Yes.  You absolutely right.  And run-time check idea proposed by Ben
is the best from the reliability point of view (of course after fixing
the typo :-)

-- 
Andrew W. Nosenko <address@hidden>