1 << length(sprintf("%b", $input))

Not fast, of course, but perfectly fine when called only once such as for a new constant (or other inlineable subs) 

use Some::Other::Module 'SOM_FLAGS_MAX';

use constant MY_FLAGS_MIN => (1<<length(sprintf("%b", SOM_FLAGS_MAX));

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In reply to Re: Power of two round up. by jimav
in thread Power of two round up. by boo_radley

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