lib{atomic, itm}/configure.tgt uses -mcpu=v9 as default for sparc

[Matthias Klose]

Am 02.06.2014 22:30, schrieb Eric Botcazou:
>> I have successfully built without the switch, but I am not sure of the
>> effects at runtime.
> 
> For sure libitm cannot work, there is a 'flushw' in config/sparc/sjlj.S.
> 
>> If V9 is indeed required, is there a way to build without those libs? Or
>> has pre V9 support been dropped at some point?
> 
> No, V8 is still supported, but nobody has ported the libraries to it.
> 
>> IMHO an efficiency enhancement should not prevent running less
>> efficiently on a supported architecture. If target triple is
>> sparcv9-*-*, the next case will match and will add the "-mcpu=v9" to
>> XCFLAGS, but adding it for non-v9 sparc-*-* targets is at least weird.
> 
> Well, V9 is about 20 years old now so defaulting to it is not unreasonable, 
> especially for all the native OSes.  But patches are of course welcome.

V9 is currently bound to 64bit, you can't build a sparc-linux-gnu compiler
defaulting to V9 without patches.  But anyway, Debian did drop the sparc port
two months ago anyway.

  Matthias