replaceTopdir :: FilePath -> FilePath -> FilePath
replaceTopdir topdir ('$':'t':'o':'p':'d':'i':'r':p) = topdir ++ p
+replaceTopdir topdir ('$':'h':'t':'t':'p':'t':'o':'p':'d':'i':'r':p)
+ = topdir ++ p
replaceTopdir _ p = p
-- Get the build info, merging the setup-config and buildinfo files.