Re: portable way to get highest bit set?

From	Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups	comp.lang.c
Subject	Re: portable way to get highest bit set?
Date	2023-10-15 01:35 -0700
Organization	A noiseless patient Spider
Message-ID	<86r0lw8erq.fsf@linuxsc.com> (permalink)
References	(5 earlier) <ug8r5q$2gqj4$1@dont-email.me> <ug9p1o$2nihu$1@dont-email.me> <86cyxgabe6.fsf@linuxsc.com> <ugfo4p$ameh$1@dont-email.me> <ugfrqs$ba5k$1@dont-email.me>

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jak <nospam@please.ty> writes:

> jak ha scritto:
>
>> Tim Rentsch ha scritto:
>>
>>> jak <nospam@please.ty> writes:
>>>
>>>> unsigned long h_bit(unsigned long val)
>>>> {
>>>>  int i;
>>>>  for(i = 0; val > 1; val /= 2, i++);
>>>>  return val << i;
>>>> }
>>>
>>> A nice compact solution.  I like the way it
>>> naturally deals with the case when val is zero.
>>
>> This is not true because if Val is 0 also the bit shifted to left
>> is, so also its result is 0.  This one of the reason why the exit
>> from the loop is greater than 1.
>
> Sorry about the answer.  I have translated your comment badly.

No worries.  I see how it works, and it's cool.

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Re: portable way to get highest bit set? jak <nospam@please.ty> - 2023-10-15 06:00 +0200
  Re: portable way to get highest bit set? jak <nospam@please.ty> - 2023-10-15 07:03 +0200
    Re: portable way to get highest bit set? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-10-15 01:35 -0700

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