[commit: ghc] master: Coments and debug tracing only (577399c)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/577399c0dfd544a613e69f0760046ec0769f33a2/ghc

>---------------------------------------------------------------

commit 577399c0dfd544a613e69f0760046ec0769f33a2
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Thu May 31 12:50:36 2018 +0100

    Coments and debug tracing only
    
    See Trac #15205


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577399c0dfd544a613e69f0760046ec0769f33a2
 compiler/typecheck/TcSimplify.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/compiler/typecheck/TcSimplify.hs b/compiler/typecheck/TcSimplify.hs
index 4024098..da78075 100644
--- a/compiler/typecheck/TcSimplify.hs
+++ b/compiler/typecheck/TcSimplify.hs
@@ -1696,6 +1696,7 @@ neededEvVars implic@(Implic { ic_given = givens
       ; traceTcS "neededEvVars" $
         vcat [ text "old_needs:" <+> ppr old_needs
              , text "seeds3:" <+> ppr seeds3
+             , text "tcvs:" <+> ppr tcvs
              , text "ev_binds:" <+> ppr ev_binds
              , text "live_ev_binds:" <+> ppr live_ev_binds ]
 
@@ -1756,6 +1757,9 @@ all done by neededEvVars.
 This led to a remarkable 25% overall compiler allocation decrease in
 test T12227.
 
+But we don't get to discard all redundant equality superclasses, alas;
+see Trac #15205.
+
 Note [Tracking redundant constraints]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 With Opt_WarnRedundantConstraints, GHC can report which