Re: Double-underline-itis

From	BartC <bc@freeuk.com>
Newsgroups	comp.lang.c
Subject	Re: Double-underline-itis
Date	2017-03-01 13:04 +0000
Organization	A noiseless patient Spider
Message-ID	<o96gp9$d8n$1@dont-email.me> (permalink)
References	<o951ti$ch6$1@dont-email.me> <87tw7doktz.fsf@bsb.me.uk> <o96c5h$l84$1@dont-email.me> <878topnpqm.fsf@bsb.me.uk>

Show all headers | View raw

On 01/03/2017 12:30, Ben Bacarisse wrote:
> BartC <bc@freeuk.com> writes:

>> You mean that
>>
>>    #define restrict
>>
>> won't work because someone could have....
>>
>> I don't even understand the problem. These are system headers,
>> designed to work with a particular implementation, so will know
>> whether 'restrict' is supported or not. What's the point of such a
>> keyword being introduced if it then goes onto use something else?
>
> Many implementations support various C standards.  As I said, you could
> include a different header for C90, C99 and so on but it's easier to
> #define __restrict__ to either nothing or restrict depending on the
> language version.

I've just come across __signed__! How many C systems don't support 'signed'?

    typedef __signed__ char __s8;
    typedef unsigned char __u8;

Is this so __signed__ could be defined as 'unsigned' according to some 
compiler option? That seems unlikely when you declaring distinct s8 and 
u8 types.

(In a file from a Linux set of includes, one of various assorted headers 
that get loaded even when just using a handful of standard headers in 
the user-code. include\asm-generic\int-ll64.h

This was just after I had to 'remove' one time.h because it didn't 
define clock(). But there were 4 other time.h files in sub-directories, 
so no worries!

What a mess these system headers are. I hadn't realised they were so 
Heath Robinson, looking like a bunch of hacks put together to meet some 
deadline, instead of something more permanent.

Anyway these headers do seem to rely heavily on the use of "__" prefixes 
absolutely everywhere. And, for some reason that I'm not sure has been 
explained yet, on "__" suffixes.)

-- 
Bartc

Thread

Double-underline-itis BartC <bc@freeuk.com> - 2017-02-28 23:44 +0000
  Re: Double-underline-itis supercat@casperkitty.com - 2017-02-28 15:54 -0800
  Re: Double-underline-itis Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-03-01 01:19 +0000
    Re: Double-underline-itis David Brown <david.brown@hesbynett.no> - 2017-03-01 09:11 +0100
    Re: Double-underline-itis BartC <bc@freeuk.com> - 2017-03-01 11:45 +0000
      Re: Double-underline-itis Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-03-01 12:30 +0000
        Re: Double-underline-itis BartC <bc@freeuk.com> - 2017-03-01 13:04 +0000
          Re: Double-underline-itis Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-03-01 15:29 +0000
            Re: Double-underline-itis gazelle@shell.xmission.com (Kenny McCormack) - 2017-03-01 15:47 +0000
          Re: Double-underline-itis Keith Thompson <kst-u@mib.org> - 2017-03-01 09:30 -0800
            Re: Double-underline-itis supercat@casperkitty.com - 2017-03-01 10:14 -0800
            Re: Double-underline-itis Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-16 18:45 -0700

csiph-web