build-depend on a recent mtl

Old versions have an insufficiently generic definition of reader,
which only works on ReaderT and not on newtypes made of it, or something
like that.

2 files changed, 6 insertions, 0 deletions

diff --git a/doc/bugs/3.20121112_build_fails_on_Ubuntu_12.04.mdwn b/doc/bugs/3.20121112_build_fails_on_Ubuntu_12.04.mdwn
index 9d743209b..cd0897649 100644
--- a/doc/bugs/3.20121112_build_fails_on_Ubuntu_12.04.mdwn
+++ b/doc/bugs/3.20121112_build_fails_on_Ubuntu_12.04.mdwn
@@ -90,3 +90,8 @@ Ubuntu 12.04 (current "long term support", all packages up to date)
 Please provide any additional information below.
 
 No idea how important this is for git-annex in general but reporting in case it is. Thank you for working on git annex!
+
+> I was able to reproduce this build error when I force installed
+> an old version of the haskell mtl library. So git-annex needs version
+> 2.1.1 to build, and I have adjusted the build dependencies appropriately.
+> [[done]] --[[Joey]] 
diff --git a/doc/install/fromscratch.mdwn b/doc/install/fromscratch.mdwn
index 49dd1302e..1aebc68a2 100644
--- a/doc/install/fromscratch.mdwn
+++ b/doc/install/fromscratch.mdwn
@@ -3,6 +3,7 @@ quite a lot.
 
 * Haskell stuff
   * [The Haskell Platform](http://haskell.org/platform/) (GHC 7.4 or newer)
+  * [mtl](http://hackage.haskell.org.package/mtl) (2.1.1 or newer)
   * [MissingH](http://github.com/jgoerzen/missingh/wiki)
   * [pcre-light](http://hackage.haskell.org/package/pcre-light)
   * [utf8-string](http://hackage.haskell.org/package/utf8-string)