Hi Ludo,

OK, here's my next attempt at a solution for this problem. :-)

Compared to the previous stack calibration patch/approach, the main
points of this one are that

- it uses a much larger amount of executed code to calibrate stack
usage: specifically, all the code involved in starting up a standard
debug-mode REPL

- it focusses on the problem of getting `make check' to pass (when it
should do so)

- it does not modify the value or meaning of the default, C-coded stack limit

- it doesn't require building the whole of Guile twice!

I'm only looking at this stage for general thoughts; if you think this
approach looks good, I will still need to

- incorporate a "-l ../libguile/stack-limit-calibration.scm" into the
running of test-suite/tests/*

- do ChangeLogs, docs and NEWS.

Please let me know what you think.

      Neil