Add build-tools Alex and Happy.

4e584418 · Andrey Mokhov · c7f8ae24 · 4e584418
Commit 4e584418 authored Sep 01, 2016 by Andrey Mokhov
--- a/hadrian.cabal
+++ b/hadrian.cabal
@@ -129,6 +129,8 @@ executable hadrian
                       , shake                >= 0.15.6
                       , transformers         >= 0.4 && < 0.6
                       , unordered-containers == 0.2.*
+    build-tools:         alex  >= 3.1
+                       , happy >= 1.19.4
    ghc-options:         -Wall
                         -fno-warn-name-shadowing
                         -rtsopts -with-rtsopts=-I0