Sun Dec 2 10:51:31 EST 2018

Automatically wrapping a black-box build

Suppose that:
- the build alrady has a pretty fast null build
- it is easy to list the targets

This way it would be possible to make a time stamp.

One way to solve it is to always tar up the results.  That gives a
single file to depend on.

I'm missing one crucial point: how to take a phony target (i.e. an
idempotent script) and turn it back into a time-stamped target?

Generalizes to hash -> timestamp.

Again: abstracting a build step requires:
- list of input files
- list of output files (could be packed to one archive)
- build script

The condition to run the script in a Makefile is done based on time
stamps.  Is there a way to:
- make that decision more abstract
- translate the abstract decision to a time stamp to plug into make

There seems to be a fundamental issue to plug this back into Make:
once something is a phony target, things are lost...

Translating an arbitrary boolean to a timestamp doesn't seem to be
possible.  It only works for recursive make, which is imperative