[commit: ghc] wip/T12357-built-in-map: DsExpr: Remove unnecessary usage of concatFS (5446684)

[git at git.haskell.org]

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

On branch  : wip/T12357-built-in-map
Link       : http://ghc.haskell.org/trac/ghc/changeset/54466843f309aa31c41ceebb0f59410dc40e5e80/ghc

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

commit 54466843f309aa31c41ceebb0f59410dc40e5e80
Author: Ben Gamari <ben at smart-cactus.org>
Date:   Fri Jul 8 16:14:29 2016 +0200

    DsExpr: Remove unnecessary usage of concatFS
    
    Producing a FastString and then immediately unpacking it is rather silly


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54466843f309aa31c41ceebb0f59410dc40e5e80
 compiler/deSugar/DsExpr.hs | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/compiler/deSugar/DsExpr.hs b/compiler/deSugar/DsExpr.hs
index 85177ee..b01b0e6 100644
--- a/compiler/deSugar/DsExpr.hs
+++ b/compiler/deSugar/DsExpr.hs
@@ -470,12 +470,10 @@ dsExpr (HsStatic _ expr@(L loc _)) = do
     mkStaticPtrFingerprint :: Module -> DsM Fingerprint
     mkStaticPtrFingerprint this_mod = do
       n <- mkGenPerModuleNum this_mod
-      return $ fingerprintString $ unpackFS $ concatFS
-        [ unitIdFS $ moduleUnitId this_mod
-        , fsLit ":"
-        , moduleNameFS $ moduleName this_mod
-        , fsLit ":"
-        , mkFastString $ show n
+      return $ fingerprintString $ intercalate ":"
+        [ unitIdString $ moduleUnitId this_mod
+        , moduleNameString $ moduleName this_mod
+        , show n
         ]
 
     mkGenPerModuleNum :: Module -> DsM Int