Compiling DMD on Windows: A journey of mystery and madness

[NX via Digitalmars-d]

[warning: rant ahead]

I'm amazed by the lack of documentation - or to say it better, 
documentation that works - on how to compile DMD and eventually 
Phobos. Here 
[https://wiki.dlang.org/Starting_as_a_Contributor#Windows_2] we 
have awfully categorized yet promising information on how to 
seriously compile DMD from source.
Before I compile dmd, I attempted to compile druntime & phobos 
and failed miserably. For God's sake no place in docs say that I 
need DMC, which is something I figured from make error output. I 
reinstalled dmd and this time I checked that box which makes 
installer automatically download and install dmc. After making 
dmc available from %path%, I was able to compile phobos, that 
seemed too good to be true. Then here comes the part about 
compiling dmd:

$ make -fwin32.mak release
This innocent looking command which supposed to compile dmd 
failed with an error message that killed my brain cells:
$ run idgen
$ Error: 'run' not found

WTF? Are we seriously trying to execute "run"? Ohh the horror!

Walking on the edge of going mad, I noticed a horrible detail in 
win32.mak file:
# D compiler (set with env variable)
#HOST_DC=dmd

The fact that HOST_DC=dmd is commented out and not being defined 
as an environment variable is shameful to the max.

After fixing make file, I was finally able to compile dmd. Now I 
want to sue D Language Foundation for dealing me mental damage. 
Thanks for reading.