I got this error,

what's this error message? unhandled constant #<procedure src (lam u)>

So a <const> with got a src meta informatoin in it's field somehow, a bug in guile's compiler 

for sure. This is for a real stress test, a compile of a huge file that used to take 10minutes to compile. So I ill not be able to track this down and make a bugreport But now you know, there 

exist a bug!

Regards

Stefan