Re: [PATCH] [RFT] m68k: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION

Hi Arnd!

On 2/25/21 12:14 PM, Arnd Bergmann wrote:

From: Arnd Bergmann <arnd@arndb.de>

While experimenting with CONFIG_TRIM_UNUSED_KSYMS across architectures,
I noticed that this unsurprisingly works best when combined with the
--gc-sections linker flag, which is not currently allowed on m68k.

Enabling it with this patch shows significant improvements
for kernel size, looking at m68k defconfig with gcc-10, I get

4005135 1374302 167108 5546545 54a231 vmlinux-normal
3916254 1378078 167108 5461440 5355c0 vmlinux+trim
4012933 1362514 164280 5539727 54878f vmlinux+gcsection
3797884 1334194 164640 5296718 50d24e vmlinux+gcsection+trim

There are probably bugs somewhere, but if someone is able to test this
patch and fix any issues that come up, would be a useful improvement
for memory-limited machines.

Thanks, that sounds like a very helpful improvement. I'll test the patch next
week when I'm on vacation and report back if it works - unless someone beats
me to it ;-).

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz@debian.org
`. `'   Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
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