RFC: Removing the `-hb` profiling option

[Erik de Castro Lopo]

Hi all,

After a bit of rather tedious and frustrating debugging I came to the
realisation that the code for the `-hb` profiling option is not thread
safe. See https://ghc.haskell.org/trac/ghc/ticket/12019

This gives us an opportunity to simply remove it instead of fixing it.
If there is anyone that thinks this future is really useful (ie more
useful than the other profiling modes) then I'm willing to fix it.
But if noone would miss it. I'd much rather remove it.

Thoughts?

Erik
-- 
----------------------------------------------------------------------
Erik de Castro Lopo
http://www.mega-nerd.com/