Re: ctype, chrtbl, rune tables and POSIX2008

[yamt%mwd.biglobe.ne.jp@localhost (YAMAMOTO Takashi)]

hi,

> On Wed, Jan 18, 2012 at 09:49:20PM +0000, YAMAMOTO Takashi wrote:
>> hi,
>> 
>> > On Tue, Jan 17, 2012 at 12:11:57AM +0000, YAMAMOTO Takashi wrote:
>> >> your suggestion is to add xlocale without uselocale, right?
>> > 
>> > Yes.
>> 
>> i'm not sure if it's a good idea because
>> 
>> - uselocale is acutally being used by third party code in the wild.
>> 
>> - uselocale is in standard.
>> 
>> - sometimes uselocale is the only choice.
>>   eg. when calling a library which internally uses locale-sensitive 
>> functions.
> 
> The problem is that it adds the TLS access overhead for all the
> locale-sensitive functions.

isn't it avoidable with a global
uselocale_has_ever_been_used_for_this_process variable?

> Further complications are added by VAX and
> Sun2 still not supporting TLS. It seems like a strong hack around for
> broken code.

can't they use a plain setspecific?

> 
>> >> is the rest of his patch ok for you?
>> > 
>> > Looking at the latest version, I don't agree with using _ all over the
>> > place. I think it would help to clean up dead code first -- is there a
>> > good reason for keeping CITRUS optional? Getting rid of that helps for
>> > all the patches in the area (ctype, multi-locale etc). After having only
>> > a single implementation, we can easily go over each function set and
>> > merge it individually.
>> 
>> the size of libc is the only reason to have it optional i'm aware of.
>> but i even don't know how much it makes libc smaller/bigger.
> 
> joerg@britannica:/tmp/with-citrus$ size libc.so.12.179 
>    text          data     bss     dec     hex filename
> 1136427         47232   65752 1249411  131083 libc.so.12.179
> 
> joerg@britannica:/tmp/without-citrus$ size libc.so.12.179 
>    text          data     bss     dec     hex filename
> 1101773         41984   63832 1207589  126d25 libc.so.12.179
> 
> That's AMD64 with Clang. Does the small difference really justify the
> complexity?

thanks for providing numbers.
it seems not worth the complexity to me.
but i guess an x86-only guy like me is not a right person to judge. :-)

i remembered another possible problem; the size of statically linked binaries.
eg. a single printf pulled in a lot of locale stuff.

YAMAMOTO Takashi

> 
> Joerg