Re: Time for a new release...

[Paul Smith]

On Sun, 2020-12-20 at 14:19 -0900, Britton Kerin wrote:
> A while back there was talk about making Make a bit smarter about
> understanding implicit dependencies make-sphere stuff:
> 
> http://gnu-make.2324884.n4.nabble.com/Idea-Add-COMMANDCHANGE-and-CACHE-td19133.html
> 
> I've come to like the idea and am curious if anything ever happened
> on this?

No, no one ever pushed that further as far as I know.  As a concept
it's not bad: similar to some things I've been thinking of although I
was thinking of using symlinks to avoid file reads... I'm not a fan of
using directories because some filesystems have limits on the number of
subdirectories.  I'm also not sure about using SHA for this; do we
really need the expense of a cryptographic hash here?  Don't we really
mostly care about uniqueness?  But these are just implementation
details.

The main thing is that once you create a concept of a "make durable
state" then there are a lot of things that you might like to have
there.  That proposal discusses the SHA of a command line, to detect
when compiler options change for example.

But, there have been other things people have wanted durable state for:
for example basing out-of-date detection on things like file content or
other attributes besides mod time.

And there are probably other things that will come up.

It seems like a not-great idea to have multiple ways of storing durable
state, so the question is can we come up with a method flexible enough
that we won't be banging our heads against it in a year.