[GHC] #13229: Add -ddump-inlinings-reasoning

[GHC]

#13229: Add -ddump-inlinings-reasoning
-------------------------------------+-------------------------------------
           Reporter:  nomeata        |             Owner:
               Type:  feature        |            Status:  new
  request                            |
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.0.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 It always takes me a while (usually by reading the source code) that
 `-ddump-inlinings` is not as useful as I want it to be without `-dverbose-
 core2core`. This just happened to me yesterday. But the latter is very
 verbose!

 In changeset:6128b2ffbe36ed2779583e05ee9d817eaafc1c9c Ben documented this
 behaviour (thanks!) but it is still annoying.

 Can we not have a flag `-ddump-inlinings-reasoning` that enables the more
 verbose variant of `-ddump-inlinings` independent of `-dverbose-
 core2core`?

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13229>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler