Why is the "linux" version identifier all lowercase?

[Nick Sabalausky]

"Walter Bright" <newshound2 at digitalmars.com> wrote in message 
news:j11hfi$10tv$1 at digitalmars.com...
> On 7/30/2011 2:05 AM, Lars T. Kyllingstad wrote:
>> http://d-programming-language.org/version.html#PredefinedVersions
>>
>> Why is the "linux" version identifier all lowercase?
>
> Because gcc's predefined macro is "linux".

If gcc defined a macro to jump off a bridge...  ;)