Re: lib/48427: libedit shouldn't require ISO 10646

[Thomas Klausner <wiz%NetBSD.org@localhost>]

The following reply was made to PR lib/48427; it has been noted by GNATS.

From: Thomas Klausner <wiz%NetBSD.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: lib/48427: libedit shouldn't require ISO 10646
Date: Sat, 7 Dec 2013 01:03:50 +0100

 On Fri, Dec 06, 2013 at 09:15:00PM +0000, yuri%rawbw.com@localhost wrote:
 > While porting lib/libedit to FreeBSD I noticed this lines in chartype.h:
 > 
 > #ifndef __STDC_ISO_10646__
 > /* In many places it is assumed that the first 127 code points are ASCII
 >  * compatible, so ensure wchar_t indeed does ISO 10646 and not some other
 >  * funky encoding that could break us in weird and wonderful ways. */
 >         #error wchar_t must store ISO 10646 characters
 > #endif
 > 
 > You limit the character set to UCS (ISO 10646) in order to make sure that 
 > lower 127 code points are ASCII. There are many character sets that satisfy 
 > this condition, and UCS is just one of them. Other practical examples are 
 > KOI8-U,KOI8-R for Cyrillic, ISO/IEC 8859-15, and some others for some other 
 > languages.
 > 
 > FreeBSD, for example, doesn't have __STDC_ISO_10646__ defined because the 
 > user can set any other character set through environment.
 > 
 > I am not sure what is the right solution, but requiring ISO 10646 isn't 
 > right, and would break compiles in general.
 
 Do I understand correctly that you're saying that what the user
 defines in the environment changes how wchar_t is defined?
  Thomas