Re: [PATCH] x86: Don't remove empty x86 properties

[Cary Coutant <ccoutant at gmail dot com>]

On Tue, Nov 27, 2018 at 4:52 AM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> On Mon, Nov 26, 2018 at 5:40 PM Cary Coutant <ccoutant@gmail.com> wrote:
> >
> > > Since empty x86 properties contain valid information, they shouldn't be
> > > removed.
> >
> > Where is this documented? How is a property consisting of all zeroes
> > different from a missing property?
> >
> > (I understand the difference for ISA_1_USED in relocatable objects --
> > an input object missing this property kills the property for the
> > output file -- but I can't find anything that says under what
> > circumstances the output property section should contain a property
> > with all zeroes.)
>
> GNU_PROPERTY_X86_ISA_1_USED bits can be all zero when only
> base x86 instructions are used.  Linker shouldn't remove properties
> with zero bits.

I'll repeat the question:

> > Where is this documented? How is a property consisting of all zeroes
> > different from a missing property?

-cary