My apologies for the delay, real life and all
I'll be uploading 6.x and 7.x toolchains today, in both Linaro and GNU variants for both ARM and ARM64.
This patch will allow Android kernels to boot with GCC 7.x and above (I won't be releasing 8.x toolchains as there is not enough differences between it and 7.x at the moment, plus I hate building from any master branch when stable is available and usable).
These will most likely not work with ROMs as they are built with glibc versus bionic. crosstool-ng has preliminary bionic support but it gave me some issues while compiling and I am not interested in hacking these to work with ROMs. I'm primarily a kernel developer so that's all I care about.
I will be uploading a crosstool-ng how to within the next week or so, there's a fair amount of info and options to go into.