[isabelle-dev] AFP continously broken

[Makarius]

In the past few days AFP has been continuously broken: presently 
AFP/3fc9e6ace21f and Isabelle/1f27d75ccf05. After some time in a bad state 
it becomes increasingly difficult to guess which changes are responsible. 
http://isabelle.in.tum.de/reports/Isabelle/shortlog provides some clues, 
but they are unsure: it looks like lifting, codegen, potentially 
codatatype.

Some years ago we used to have broken AFP states routinely, in 
correspondance to full-day test time.  Now that is around 1h, so there is 
hardly a reason of not testing frequently, especially in conjunction with 
pushes on main Isabelle. Time is better invested to test directly 
(isabelle build -a -d '$AFP') instead of making remote guesses.


 	Makarius