Adding ccache-like output caching to dmd

[John Colvin]

On Tuesday, 29 December 2020 at 20:09:25 UTC, John Colvin wrote:
> On Tuesday, 29 December 2020 at 19:57:21 UTC, Per Nordlöw wrote:
>> On Tuesday, 29 December 2020 at 16:43:33 UTC, John Colvin 
>> wrote:
>>> Or something like that, you get the idea... It's not 
>>> intractable, it's just a bit fiddly.
>>
>> Superb answer.
>>
>> Does this design match https://github.com/dlang/dub/pull/2044
>
> Not really, although maybe it should?
>
> If I understand correctly (I haven't reviewed the 
> implementation), that PR is using dub's normal rebuild rules 
> w.r.t. changed files and is just swapping out access times for 
> content hashes. Maybe I'm mistaken, but I don't think dub pays 
> any attention to changes in files that aren't source files.

s/access times/modification times/
s/source files/in sourceFiles\/sourcePaths/