Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > alt.comp.lang.c > #611
| From | Keith Thompson <Keith.S.Thompson+u@gmail.com> |
|---|---|
| Newsgroups | comp.lang.c, alt.comp.lang.c |
| Subject | Re: portable way to get highest bit set? |
| Date | 2023-10-11 14:30 -0700 |
| Organization | None to speak of |
| Message-ID | <87h6mwu9rk.fsf@nosuchdomain.example.com> (permalink) |
| References | <ug5gvh$1jkar$3@dont-email.me> <pan$e0805$faa9a91a$a60476dc$4a90cfa8@invalid.invalid> |
Cross-posted to 2 groups.
Blue-Maned_Hawk <bluemanedhawk@invalid.invalid> writes:
> candycanearter07 wrote:
>> What is the best/most portable way to get the highest bit set?
>>
>> ie. 011010001 to 010000000
>
> #include <stdbit.h>
>
> unsigned char highest_bit_setc(unsigned char x)
> {
> return stdc_first_leading_one(x) ? (1 << stdc_first_leading_one(x)
> - 1) : 0;
> }
>
> /* Repeat for all appropriate types and then probably make a generic macro
> for all the subroutines. */
A solution that depends on a header that's introduced in C23, a standard
that hasn't been published yet, is hardly portable.
BTW, here's what your signature looks like in my newsreader (Gnus):
Blue-Maned_HawkÃ\203\203\203\203Ã\203\203\202Ã\203\202Ã\202¢\224\202shortens to
HawkÃ\203\203\203\203Ã\203\203\202Ã\203\202Ã\202¢\224\202/
blu.mÃ\203\203\203\203\211\233in.dÃ\203\203\203\203\212Ã\203\203\203\202Ã\203\203\202Ã\203\202Ã\202°ak/
Ã\203\203\203\203Ã\203\203\202Ã\203\202Ã\202¢\224\202he/him/his/himself/Mr.
bluemanedhawk.github.io
Minor vehicular events!
And in Thunderbird:
Blue-Maned_HawkÃÃÃâshortens to
HawkÃÃÃâ/
blu.mÃin.dÃÃÃÃðak/
ÃÃÃâhe/him/his/himself/Mr.
bluemanedhawk.github.io
Minor vehicular events!
--
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */
Back to alt.comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar
portable way to get highest bit set? candycanearter07 <no@thanks.net> - 2023-10-11 01:56 -0500
Re: portable way to get highest bit set? Anton Shepelev <anton.txt@g{oogle}mail.com> - 2023-10-11 10:27 +0300
Re: portable way to get highest bit set? David Brown <david.brown@hesbynett.no> - 2023-10-11 11:31 +0200
Re: portable way to get highest bit set? Anton Shepelev <anton.txt@g{oogle}mail.com> - 2023-10-11 12:33 +0300
Re: portable way to get highest bit set? David Brown <david.brown@hesbynett.no> - 2023-10-11 13:58 +0200
Re: portable way to get highest bit set? Anton Shepelev <anton.txt@g{oogle}mail.com> - 2023-10-11 15:17 +0300
Re: portable way to get highest bit set? David Brown <david.brown@hesbynett.no> - 2023-10-11 16:22 +0200
Re: portable way to get highest bit set? Anton Shepelev <anton.txt@g{oogle}mail.com> - 2023-10-11 18:08 +0300
Re: portable way to get highest bit set? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-11 17:20 +0100
Re: portable way to get highest bit set? David Brown <david.brown@hesbynett.no> - 2023-10-11 18:28 +0200
Re: portable way to get highest bit set? candycanearter07 <no@thanks.net> - 2023-10-11 11:19 -0500
Re: portable way to get highest bit set? David Brown <david.brown@hesbynett.no> - 2023-10-11 18:45 +0200
Re: portable way to get highest bit set? Ian C <deathstation9000@gmail.com> - 2023-10-11 18:03 +0100
Re: portable way to get highest bit set? candycanearter07 <no@thanks.net> - 2023-10-11 19:26 -0500
Re: portable way to get highest bit set? Richard Harnden <richard.nospam@gmail.invalid> - 2023-10-11 19:02 +0100
Re: portable way to get highest bit set? candycanearter07 <no@thanks.net> - 2023-10-11 19:25 -0500
Re: portable way to get highest bit set? Bart <bc@freeuk.com> - 2023-10-12 01:35 +0100
Re: portable way to get highest bit set? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-10-11 17:50 -0700
Re: portable way to get highest bit set? candycanearter07 <no@thanks.net> - 2023-10-11 20:03 -0500
Re: portable way to get highest bit set? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-11 13:56 +0100
Re: portable way to get highest bit set? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2023-10-11 14:54 +0000
Re: portable way to get highest bit set? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2023-10-12 23:35 +0000
Re: portable way to get highest bit set? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2023-10-12 23:47 +0000
Re: portable way to get highest bit set? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-11 17:23 +0000
Re: portable way to get highest bit set? jak <nospam@please.ty> - 2023-10-11 22:26 +0200
Re: portable way to get highest bit set? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-11 23:58 +0100
Re: portable way to get highest bit set? jak <nospam@please.ty> - 2023-10-12 09:14 +0200
Re: portable way to get highest bit set? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-12 10:50 +0100
Re: portable way to get highest bit set? jak <nospam@please.ty> - 2023-10-12 13:35 +0200
Re: portable way to get highest bit set? Michael S <already5chosen@yahoo.com> - 2023-10-12 15:36 +0300
Re: portable way to get highest bit set? jak <nospam@please.ty> - 2023-10-12 15:18 +0200
Re: portable way to get highest bit set? jak <nospam@please.ty> - 2023-10-12 15:09 +0200
Re: portable way to get highest bit set? jak <nospam@please.ty> - 2023-10-12 23:39 +0200
Re: portable way to get highest bit set? Blue-Maned_Hawk <bluemanedhawk@invalid.invalid> - 2023-10-11 21:16 +0000
Re: portable way to get highest bit set? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-10-11 14:30 -0700
Re: portable way to get highest bit set? Blue-Maned_Hawk <bluemanedhawk@invalid.invalid> - 2023-10-12 13:42 +0000
Re: portable way to get highest bit set? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-10-12 14:30 -0700
Re: portable way to get highest bit set? Anton Shepelev <anton.txt@gmail.moc> - 2023-10-13 00:50 +0300
Re: portable way to get highest bit set? "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-12 16:17 -0700
Re: portable way to get highest bit set? vallor <vallor@cultnix.org> - 2023-10-13 20:12 +0000
Re: 🏳️🌈portable way to get highest bit set?🏳️🌈 🌈💐🌻🌺🌹🌻💐🌷🌺🌈Jen🌈💐🌻🌺🌹🌻💐🌷🌺🌈 Dershmender 💐🌻🌺🌹🌻💐🌷🌺🐶笛🌈💐🌻🌺🌹🌻💐🌷🌺🌈 <root@127.0.0.1> - 2023-10-17 18:28 +0000
Re: portable way to get highest bit set? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-11 21:57 +0000
Re: portable way to get highest bit set? Kaz Kylheku <864-117-4973@kylheku.com> - 2023-10-15 05:26 +0000
Re: portable way to get highest bit set? Michael S <already5chosen@yahoo.com> - 2023-10-15 11:35 +0300
Re: portable way to get highest bit set? yeti <yeti@tilde.institute> - 2023-10-15 14:26 +0000
csiph-web