Re: Linux/Clang/Libobjc2 failure part 2 (ng)

[David Chisnall]

On 24 Jun 2018, at 17:27, Fred Kiefer <fredkiefer@gmx.de> wrote:
> 
> Hi David,
> 
>> Am 24.06.2018 um 11:17 schrieb David Chisnall <gnustep@theravensnest.org>:
>> 
>> This isn’t needed with the v2 ABI, but I need help fixing the issues with 
>> GNUstep’s NSString implementation before I can recommend enabling that for 
>> GNUstep, because the new NSConstantString representation exposes a lot of 
>> bugs in -base’s unicode string handling.
> 
> 
> I am willing to help you with this. As far as I understand some of methods on 
> NSString are not properly implemented based on the two primitive methods 
> length and characterAtIndex:. Here it would help if you pointed me to the 
> already known incomplete methods. I am not planing to use clang or your new 
> libobjc branch so I will have to work without testing, just by code 
> inspection.

I’ve done some things in the newabi branch that get the correct behaviour, but 
almost certainly at the cost of performance (and I don’t have anything that is 
particularly string-intensive to benchmark with to evaluate this) by just using 
libicu to implement the concrete subclass and providing a few wrappers.  You 
can test for correctness quite easily by disabling the GS special cases and 
checking the test suite.  

David