[GHC] #15524: Performance regression when using the GHC API to evaluate code compared to 8.4

[GHC]

#15524: Performance regression when using the GHC API to evaluate code compared to
8.4
-------------------------------------+-------------------------------------
           Reporter:  vaibhavsagar   |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:  8.6.1
          Component:  Compiler       |           Version:  8.6.1-beta1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  Runtime
  Unknown/Multiple                   |  performance bug
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 I've been in the process of updating IHaskell to support GHC 8.6 and the
 test suite has become agonisingly slow as compared to GHC 8.4 and below.
 I've been able to work around this by using `--enable-executable-dynamic`
 as suggested by `christiaanb` on `#ghc`but I thought this was worth
 reporting as a bug. I am using `ghc-8.6.1-alpha2` so it's possible that
 this has been fixed in `beta1`.

 To reproduce this on a Linux installation with Nix:

 1. `git clone https://github.com/gibiansky/IHaskell --branch support-
 ghc-8-6 repro`
 2. `cd repro`
 3. Comment out `--enable-executable-dynamic` in `release-8.6.nix`
 4. `nix-build release-8.6.nix`

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15524>
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