automatic regeneration for all of this template substitution, and for
config.status etc. is done for you.
+Summary of directory reference syntaxes
+---------------------------------------
+
+ In build tree In source tree
+ Relative Absolute Relative Absolute
+
+ &file $(abs)/&file
+ This directory &/file $(abs)/&/file &^/file &~/file
+ & f g h & ^ f g h & ~ f g h
+
+ Top level file $(abs)/file $(ts)/file $(ats)/file
+ f g h
+
Substitution syntax
-------------------