Segher Boessenkool [off-list ref] writes:

On Thu, Jul 18, 2019 at 11:19:58AM +0900, Masahiro Yamada wrote:

quoted

On Thu, Jul 18, 2019 at 1:46 AM Segher Boessenkool
[off-list ref] wrote:
Kbuild always uses thin archives as far as vmlinux is concerned.

But, there are some other call-sites.

masahiro@pug:~/ref/linux$ git grep  '$(AR)' -- :^Documentation :^tools
arch/powerpc/boot/Makefile:    BOOTAR := $(AR)
arch/unicore32/lib/Makefile:    $(Q)$(AR) p $(GNU_LIBC_A) $(notdir $@) > $@
arch/unicore32/lib/Makefile:    $(Q)$(AR) p $(GNU_LIBGCC_A) $(notdir $@) > $@
lib/raid6/test/Makefile:         $(AR) cq $@ $^
scripts/Kbuild.include:ar-option = $(call try-run, $(AR) rc$(1)
"$$TMP",$(1),$(2))
scripts/Makefile.build:      cmd_ar_builtin = rm -f $@; $(AR)
rcSTP$(KBUILD_ARFLAGS) $@ $(real-prereqs)
scripts/Makefile.lib:      cmd_ar = rm -f $@; $(AR)
rcsTP$(KBUILD_ARFLAGS) $@ $(real-prereqs)

Probably, you are interested in arch/powerpc/boot/Makefile.

That one seems fine actually.  The raid6 one I don't know.


My original commit message was

    Without this, some versions of GNU ar fail to create
    an archive index if the object files it is packing
    together are of a different object format than ar's
    default format (for example, binutils compiled to
    default to 64-bit, with 32-bit objects).

but I cannot reproduce the problem anymore.  Shortly after my patch the
thin archive code happened to binutils, and that overhauled some other
things, which might have fixed it already?

quoted

quoted

Yes, I know.  This isn't about built-in.[oa], it is about *other*
archives we at least *used to* create.  If we *know* we do not anymore,
then this workaround can of course be removed (and good riddance).

If it is not about built-in.[oa],
which archive are you talking about?

Can you pin-point the one?

No, not anymore.  Lost in the mists of time, I guess?  I think we'll
just have to file it as "it seems to work fine now".

Yeah I think so. If someone finds a case it breaks we can fix it then.

Thank you (and everyone else) for the time looking at this!

Likewise.

cheers