>> The C files more or less directly involved in byte-compilation are, I
>> think, eval.c, data.c, alloc.c, lread.c, bytecode.c.  If we think one
>> of these could be involved, it would be nice to find the one(s) that
>> cause the problem, for example, by selectively compiling only those
>> with -fno-optimize-sibling-calls, then removing them one by one from
>> the set of files compiled like that.
>
> That would be a good starting point already, I'd suggest to add comp.c
> to the investigated set as well.

I can take a look into this, but I'm unsure as to how exactly; I'm still
very new to the GNU Autotools. AFAIU, this would be done using
per-target Automake variables but there's no Makefile.am...