> Is it really worth it?
> You are making life easier for a "clever user" ...
I am eliminating a possible cause of "handler_fault...". The cost is 5 lines
> at the expense of making an additional system call for everyone else!
alloca(1) is a single machine instruction, not a system call. And it occurs
in an "if (never_never)" branch of code.
> Moreover, __EVEN WITH__ this alloca() trick, clisp segfaults on the
> first GC on mingw
Is is related?
> how is this better than just removing the alloca() trick and putting a
> note in INSTALL that -fomit-frame-pointer is not supported?
It reduces the number of things that an installer must be aware of, by 1.
> Let us be consistent: if we want -fomit-frame-pointer to work - at
> least sometimes - keep the trick and add -fomit-frame-pointer in
> makemake.in (conditional on mingw where it does not work now).
This is not about being consistent. It's about safety and speed.
Since our measurements indicate the -fomit-frame-pointer brings
absolutely no speed advantage, why should I add it back to makemake.in?
> if we do not want it - remove all vestiges of it.
No. We don't recommend -fomit-frame-pointer but we don't forbid it either.
Similarly, we don't recommend gcc-2.7.2, but we don't forbid it either.