Add `-haddock` option under ci condition to fix #16415
In order to use the :doc
command in ghci, it is necessary
to compile for core libraries with -haddock
option.
Especially, the -haddock
option is essential for release building.
Note:
- The
-haddock
option may affect compile time and binary size. But hadrian has already set-haddock
as the default.- This patch affects the make-based building.
This patch has been split from !532 (closed).