[CM] C Stack Unwinding

[Woody Douglass]

Cool! thanks so much!

One thing I have noticed in my testing today is that

    result1 = s7_call_with_catch(s, tag, make_func, catch);

behaves differently from

    result1 = s7_eval_c_string(s, "(catch #t bad-func error-handler)");

now. I suspect that one (or more) of the 

    catch_cstack(p) = NULL;

lines i added to s7.c needs to change, but i'm not sure which (all?)

I'll have more information in the morning, i'm still wrapping my head
around it. Thanks again for merging!

-Woody

On Wed, 2021-11-10 at 13:08 -0800, bil at ccrma.Stanford.EDU wrote:
> I merged in your changes, and they pass all my bazillion
> tests.  One timing test is 2% slower -- callgrind
> blames fprintf, but there is no fprintf!  I made other
> changes, so this is probably something unrelated to
> your code.  Thanks again for the improvement!
>