Re: [Ada] Lock-free implementation of protected objects

[Arnaud Charlet <charlet at adacore dot com>]

> > This patch implements a check in the runtime library that determines
> > whether
> > the current target supports the atomic primitives up to 64 bits.
> 
> If I understand the name of the flag, it looks like an "all or nothing" for
> atomic primitives?

Right.

> is that a consequence of the language definition, or simply that it isn't
> worth spending a lot of effort on 32 bit machines?

The latter for now.

> > This should fix build failures on e.g. powerpc-darwin.
> 
> almost :-)
> 
> On a 64-bit processor, the [32 bit] powerpc-darwin kernel is capable of
> launching 64bit processes.
> Thus, there is an m64 multi-lib for powerpc-darwin, which is built by
> default for GCC (and, for that multi-lib, the 64 bit locks are available).  At
> present, bootstrap is failing while building this multi-lib.
> 
> With the following, bootstrap completed on powerpc-apple-darwin9, and
> make check-ada shows no new fails.
> Should I apply it?

Looks good to me, go ahead, although I'm a bit surprised that you got an error,
can you clarify what error you got?

> Iain
> 
> gcc/ada: 
> 
> 	* system-darwin-ppc64.ads: Add Support_Atomic_Primitives,
> 	set to True.