QUOTE doesn't make sense to me.
How about:
#!+(and (not (host-feature :sb-sb-host)) ...)

On Mon, Sep 16, 2013 at 12:39 PM, Faré <fahree@gmail.com> wrote:
On Mon, Sep 16, 2013 at 11:02 AM, Douglas Katzman <dougk@google.com> wrote:
> 2. Avoid nesting of the macros - it's not very clear.  If the #! reader were
> to understand :sb-xc-host as a special-case, treating it as if it were a
> target feature, then the conditionalized form
>      #-sb-xc-host
>      #!+#.(cl:if ....)
>      ((simple-array (unsigned-byte 63) (*)) ...)
> could be written as
>      #!+(and (not sb-xc-host) :64-bit)
>      ((simple-array (unsigned-byte 63) (*)) ...)
Alternatively, an escape from #!+ to distinguish target from host features,
e.g. 'foo or (quote :foo) to signify not-the-default, might do wonders.

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