[commit: ghc] wip/nfs-locking: Make error message more helpful. (b4f0b5c)

[git at git.haskell.org]

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

On branch  : wip/nfs-locking
Link       : http://ghc.haskell.org/trac/ghc/changeset/b4f0b5c264583fbd2410fd3d720fa9004f0490b9/ghc

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

commit b4f0b5c264583fbd2410fd3d720fa9004f0490b9
Author: Andrey Mokhov <andrey.mokhov at gmail.com>
Date:   Fri Jan 15 14:48:29 2016 +0000

    Make error message more helpful.
    
    [skip ci]


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

b4f0b5c264583fbd2410fd3d720fa9004f0490b9
 src/Builder.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Builder.hs b/src/Builder.hs
index 353c00f..96cb608 100644
--- a/src/Builder.hs
+++ b/src/Builder.hs
@@ -93,9 +93,9 @@ builderKey builder = case builder of
 -- TODO: Paths to some builders should be determined using 'defaultProgramPath'
 builderPath :: Builder -> Action FilePath
 builderPath builder = do
-    path <- askConfigWithDefault (builderKey builder) $
-            putError $ "\nCannot find path to '" ++ (builderKey builder)
-                     ++ "' in configuration files."
+    path <- askConfigWithDefault (builderKey builder) . putError $
+        "\nCannot find path to '" ++ (builderKey builder)
+        ++ "' in configuration files. Have you forgot to run configure?"
     windows <- windowsHost
     case (path, windows) of
         ("", _)    -> return path