On Thu, 11 Aug 2016 15:04:00 +0200
Arnd Bergmann [off-list ref] wrote:

On Thursday, August 11, 2016 10:43:20 PM CEST Nicholas Piggin wrote:

quoted

On Wed, 03 Aug 2016 22:13:28 +0200

quoted

Final ld time
inclink
real	0m0.378s
user	0m0.304s
sys	0m0.076s

thinarc
real    0m0.894s
user    0m0.684s
sys     0m0.200s  

This also still seems fine.

quoted

For both cases final link gets slower with thin archives. I guess there is some
per-file overhead but I thought with --whole-archive it should not be that much
slower. Still, overall time for main ar/ld phases comes out about the same in
the end so I don't think it's too much problem. Unless ARM blows up significantly
worse with a bigger config.  

Unfortunately I think it does. I haven't tried your latest series yet,
but I think the total time for removing built-in.o and relinking went
up from around 4 minutes (already way too much) to 18 minutes for me.

quoted

Linking with thin archives takes significantly more time in bfd hash lookup code.
I haven't dug much further yet.  

Can you try the ARM allyesconfig with thin archives? I'll follow up with two
patches: one to get ARM to link without thin archives, and one that I used
to get --gc-sections to work.

Okay send them over, I'll try digging into it. There is not much kbuild
code to maintain so we don't have to switch every arch. It would be nice
to though.

Thanks,
Nick