[SeaBIOS] Re: [PATCH 1/4] Make rom16.o linkable with lld

[Fangrui Song]

On 2020-04-06, Kevin O'Connor wrote:
> On Wed, Apr 01, 2020 at 10:29:12AM -0700, Fangrui Song wrote:
> > (1) In romlayout.S, .fixedaddr.\addr sections do have not the SHF_ALLOC flag.
> > It does not make sense to reference a SHF_ALLOC section from a non-SHF_ALLOC section via R_386_PC16.
> > GNU ld allows it but lld will warn. Add the SHF_ALLOC flag.
> >
> > (2) lld requires output section descriptions to be sorted by address.
> >  Just sort the addresses beforehand.
>
> This looks like it should be two separate patches.
>
> I know it's a pain to redo patches, but separating out changes helps
> greatly when tracking down regressions via "git bisect".

I would hope [PATCH 2/4] Makefile: Change ET_EXEC to ET_REL so that lld can link bios.bin.elf
can be applied first it it is acceptable.

Like I said, these 1~3 have no dependency at all.
Redoing a patch series and resending as a whole may mess up the list.
> > Signed-off-by: Fangrui Song
> >
> > scripts/layoutrom.py | 4 ++++
> >  src/romlayout.S      | 2 +-
> >  2 files changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/scripts/layoutrom.py b/scripts/layoutrom.py
> > index 6616721..4c55390 100755
> > --- a/scripts/layoutrom.py
> > +++ b/scripts/layoutrom.py
> > @@ -321,6 +321,10 @@ def outXRefs(sections, useseg=0, exportsyms=[], forcedelta=0):
> >
> > # Write LD script includes for the given sections
> >  def outSections(sections, useseg=0):
> > if useseg:
> >    sections.sort(key=lambda x: x.finalsegloc)
> > else:
> >    sections.sort(key=lambda x: x.finalloc)
>
> This looks odd to me - there shouldn't be a need to change the sort
> order based on useseg, as finalloc should always have the same order
> as finalsegloc.  Also, this code alters the input list which is
> confusing - perhaps use "sections = sorted(sections, key=...)".

Just to confirm, I should use:

if not useseg:
     sections = sorted(sections, key=lambda x: x.finalloc)
> >  out = ""
> >  for section in sections:
> >      loc = section.finalloc
> >
> > diff --git a/src/romlayout.S b/src/romlayout.S
> > index c4a4635..a854783 100644
> > --- a/src/romlayout.S
> > +++ b/src/romlayout.S
> > @@ -587,7 +587,7 @@ entry_18:
> >      // Specify a location in the fixed part of bios area.
> >      .macro ORG addr
> >    .section .fixedaddr.\addr
> >    .section .fixedaddr.\addr,"a"
> >    .endm
> >
> >    ORG 0xe05b