Re: Stack calibration

[Ludovic Courtès]

Hello,

Sorry for the latency...

"Neil Jerram" <address@hidden> writes:

> FWIW, I'm actually thinking now that this stack calibration stuff is
> becoming way too tricky, in at least two ways.
>
> 1) The concept of the 'stack debug option being expressed in terms of
> some other "canonical" combination of OS, compiler and compiler
> optimization level.  (I struggle to describe this clearly, here, and
> in comments in the code, and I'm sure I would struggle in the manual
> too - so that's a bad sign!)

That doesn't strike me as a bad idea.  "Portable Scheme stack
measurement unit" would be a good description, wouldn't it?

> 2) The complexity that my latest patch adds to the Guile build
> process.  And even with this complexity we still don't cover all the
> cases (notably cross compiling).

Yeah, that's the main issue.  Building all of libguile twice isn't
acceptable IMO.

> Taking everything together, my thinking now is...
>
> - The problem we actually need to solve is getting a stack overflow
> while running make and/or make check, and there may be other ways of
> doing that than trying to pick the right number, and to interpret that
> number such that it has the same effect on all platforms.

You mean "is *not* getting a stack overflow", right?

>From that point of view, adding the right `eval-set!' incantation
somewhere in the test suite would suffice to fix the problem.

> - Based on [2], it sounds like there is part of this issue that we
> don't yet understand - i.e. not just the stack growing bigger than the
> default 20000 words.

What makes you say so?  The message just shows that the test suite
sometimes triggers a stack overflow.

Thanks,
Ludo'.