Re: CHECK_STRUCTS/dmpstruct.h mechanism is broken.

[Eli Zaretskii]

> Date: Thu, 11 Apr 2019 15:13:10 -0700
> From: "Daniel Colascione" <address@hidden>
> Cc: "Paul Eggert" <address@hidden>,
>  address@hidden
> 
> > You want to test for system-dependent features with Make?  How does
> > one do that?  All those HAVE_foo macros in the sources -- how do you
> > compute them with Make?  Wouldn't we end up with heaps of Make
> > wizardry only a few understand?
> 
> GNU make can run arbitrary shell commands. You'd just write
> 
>   HAVE_foo := $(shell ./test-foo)

You can also just use the shell.  Wait, didn't Autoconf start like
that?

More seriously, there are build systems out there which don't use
Autoconf.  My limited experience with some of them is that they all
bump into the same problems of complexity when catering to large
packages that need to support many different platforms.  So it all
boils down to a different syntax (and in many cases inadequate
documentation).  A faster execution doesn't justify the massive effort
required for mastering any such new system, IME.

> Someday, it'd be nice to get rid of explicit byte compilation entirely and
> rely on either a JIT or automatic recompilation on load.

JIT byte compilation is just one part of slow part of the build.  But
even with this, the last attempt to bring JIT to Emacs stalled at a
point where it isn't yet usable except as POC, and I didn't actually
see any tangible speedup from using it when it did work.