Re: Re: go support (was: Best place to discuss other lightweight libraries?)

[Rich Felker <dalias@aerifal.cx>]

On Wed, Apr 24, 2013 at 03:28:48PM +0200, John Spencer wrote:
> On 04/24/2013 01:18 PM, Daniel Cegiełka wrote:
> >
> >btw. has anyone used go with musl?
> >
> 
> i tried to build gcc 4.7.2 with go support (--enable-languages=c,c++,go)
> and that fails due to a lack of set/getcontext().
> (see pkg/gcc472 in sabotage)
> 
> according to rich, adding that to musl requires a non-trivial amount
> of arch specific asm.

Yes, but it is a wanted feature, so I wouldn't mind it getting done.
It was even part of the standard prior to POSIX 2008, and the reason
for removing it was stupid. (The reason was that the makecontext
function's calling convention is bogus and impossible to support
properly, but they could have fixed this by deprecating the use of the
variadic arguments in any way except passing a single void* argument,
rather than deprecating the whole set of interfaces.)

> the go runtime in the gcc tree should be fixed to have a fallback
> when this functionality is missing (if possible),
> so it maybe be needed to ask on the go mailing list.

The only fallback is to use C11 or POSIX threads in place of
coroutines, or shipping their own set/getcontext code for each arch...

Rich