On Dec 19, 2018, at 2:25 PM, Andrew Martin <andrew.thaddeus@gmail.com> wrote:

How does one go about using -ddump-simpl -dsuppress-all -ddump-to-file (or variations of this) when building base?

Add a line like 

GhcLibHcOpts       += -ddump-simpl -dsuppress-all -ddump-to-file

at the end of your build.mk. You can see other similar options in the files in the flavours subdirectory of the mk directory.

I hope this helps!
Richard