Add submodules

[mspang]

As we start to add other build systems, we should have a way to sync the
project without depending on makefiles. Use git submodules for this.

This also avoids an issue with branch based dependency management
where it's not possible to fully recreate historical versions, which necessarily
includes the state of dependencies. Tracking prior versions is the main
purpose of source control.

[chip-bot]

Size increase report for "Build Examples [nRF]"

File	Section	File	VM

Full report output

Bloat report for job 'Build Examples [nRF]'

Files found only in the baseline:
    bloat_report.txt

Comparing master_binaries/nrf-build/chip-nrf52840-lock-example.out and example_binaries/nrf-build/chip-nrf52840-lock-example.out:

sections,vmsize,filesize

[chip-bot]

Size increase report for "Build Examples [ESP32]"

File	Section	File	VM
chip-wifi-echo.elf	.dram0.bss	0	8
chip-wifi-echo.elf	.dram0.data	-8	-8

Full report output

Bloat report for job 'Build Examples [ESP32]'

Files found only in the baseline:
    bloat_report.txt

Comparing master_binaries/esp32-build/chip-wifi-echo.elf and example_binaries/esp32-build/chip-wifi-echo.elf:

sections,vmsize,filesize
.dram0.bss,8,0
[Unmapped],0,8
.dram0.data,-8,-8

[chip-bot]

Size increase report for "Build Examples [main-build]"

File	Section	File	VM

Full report output

Bloat report for job 'Build Examples [main-build]'

Files found only in the baseline:
    bloat_report.txt

Comparing master_binaries/main-build/chip-standalone-demo.out and example_binaries/main-build/chip-standalone-demo.out:

sections,vmsize,filesize

[woody-apple]

@rwalker-apple ?

[gerickson]

The reason that submodules were not employed in the first place is that if you were to make dist a CHIP repo and then attempt to use it, you'd find that there is no git repository against which the git submodules can operate. Do we have a proposed solution for that?

[mspang]

Couldn't "make dist" just ship the .gitmodules and use it from bootstrap? And while we are in git, we can use it natively.

Is it expected to be a common use case to go the "make dist" route without using a separate package manager to provide the dependencies?

[gerickson]

Couldn't "make dist" just ship the .gitmodules and use it from bootstrap? And while we are in git, we can use it natively.

Is it expected to be a common use case to go the "make dist" route without using a separate package manager to provide the dependencies?

Just like with most open source packages today, if I were wanting to kick the tires on CHIP, I'd take a named archive distribution, download it, and start playing with it, as-is. Only if I found a bug or wanted to start getting deeper than kicking the tires would I bother with a repo clone.