basic asm and memory clobbers - Proposed solution

[Segher Boessenkool]

On Tue, Dec 01, 2015 at 08:41:22PM -0700, Jeff Law wrote:
> Isn't "asm" conditionally supported for ISO C++?  In which case it's not 
> mandatory and semantics are implementation defined.

Yes.

> My strong preference is still to document the desired semantics for GCC 
> and treat anything that does not adhere to those semantics as a bug.

I agree, but I think the semantics should be what they currently are.
If we want a "clobbers everything" version we could make a new syntax
for that, so that not all current asm-without-operands has to pay the
hefty price.

> I think a non-default warning is fine.  A default warning (or 
> -Wall/-Westra) is probably undesirable, though I'm still willing to be 
> convinced either way on that.

I don't think the warning is a good idea until we have decided what
direction we want this to go in.


Segher