similar idea, slightly shorter :) 
  DB<10> p length sprintf '%b',-1
64

[download]

but reliability may be effected by various math pragmas ...

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re^2: Best way to check for 64-bit support by LanX
in thread Best way to check for 64-bit support by gflohr

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