Re: gcc feature request / RFC: extra clobbered regs

[Jakub Jelinek <jakub@redhat.com>]

On Wed, Jul 01, 2015 at 01:35:16PM -0400, Vladimir Makarov wrote:
> Actually it raise a question for me.  If we describe that a function
> clobbers more than calling convention and then use it as a value (assigning
> a variable or passing as an argument) and loosing a track of it and than
> call it.  How can RA know what the call clobbers actually.  So for the
> function with the attributes we should prohibit use it as a value or make
> the attributes as a part of the function type, or at least say it is unsafe.
> So now I see this as a *bigger problem* with this extension.  Although I
> guess it already exists as we have description of different ABI as an
> extension.

Unfortunately target attribute is function decl attribute rather than
function type.  And having more attributes affect switchable targets will be
non-fun.

	Jakub