Is there a reason for updating this to 8.5.0 instead of 12.2.0 12.3?

I believe there is a known bug that causes a relative massive increase in code size with newer gcc versions which makes it difficult to fit binaries on small ECs and the like.

In D14188#243337, @joebonrichie wrote:

I believe there is a known bug that causes a relative massive increase in code size with newer gcc versions which makes it difficult to fit binaries on small ECs and the like.

If we're talking about the same bug (this one) it should be fixed for GCC 12.3+.

In D14188#243352, @silke wrote:

In D14188#243337, @joebonrichie wrote:

I believe there is a known bug that causes a relative massive increase in code size with newer gcc versions which makes it difficult to fit binaries on small ECs and the like.

If we're talking about the same bug (this one) it should be fixed for GCC 12.3+.

Awesome, we'll leave it up to chax to make sure it's all good then

Yes, that bug was fixed but QMK can't be built with avr-gcc newer than 8.x, so i decided to stay on that branch an use latest release from that branch. Of course QMK is not the only thing people use this toolchain for but updating it would definitely break it for QMK users. On the other hand older microcontroller code would also need to be adjusted to work with newer gcc compiler so it would break it for those users also. Currently i don't see any harm in keeping it on 8.x branch but i do in updating to latest 13.x branch.