Removing hardcoded hashes from Nix flake.

[rslawson]

Previously the flake would require periodically updating the commit hashes for the submodules (and their submodules, etc.). However, the flake should now handle changes to those without direct user interaction.

[maliberty]

@donn any concerns here? Nix support is for OL2 so I have none.

[rslawson]

My apologies, forgot to update the workflows. Any time the submodules update the flake.lock also needs to be updated, so I think(?) I've done that appropriately here.

[rslawson]

It would also appear that despite trying to make sure that flake.lock stays up-to-date I pushed a broken version of it. I'll push a fix for that shortly.

EDIT: Never mind, something was just odd when I cloned it to another machine - it didn't get the right submodule commits for some reason. In the morning I'll rebase on master to ensure that it works with the project in its current state.

[donn]

This is ORFS, not OpenROAD, but the changes look broadly fine

[rslawson]

This is ORFS, not OpenROAD, but the changes look broadly fine

I'm aware, yes. What do you mean by that, though?

[maliberty]

This is ORFS, not OpenROAD, but the changes look broadly fine

I'm aware, yes. What do you mean by that, though?

I think he is pointing out the OL2 only uses the nix file from OR and not ORFS.

[maliberty]

@vvbandeira do you understand the scan's error SyntaxWarning: invalid escape sequence '\('? I've never seen that before and there is no recent change.

[rslawson]

Forgive my ignorance here, but OL2? If this is in reference to the fact that I added inputs to all the submodules for OpenROAD and YoSys, that's just for reasons of Nix flakes are... interesting at times, to put it kindly. It's a workaround for an issue with submodules in flake dependencies.

[maliberty]

OL2 = OpenLane2 (https://github.com/efabless/openlane2)

[rslawson]

Oh, should I have included that instead of or in addition to OpenROAD in this? If so, I can work on that.

[donn]

@rslawson ORFS and OpenLane 2 are two different implementations of the OpenROAD flow. You're contributing to ORFS right now, so you don't need to worry about OpenLane 2.

If you were contributing to OpenROAD's Nix file, I would indeed need to take a look at that.

[rslawson]

Ah, undersood. Thank you for clearing that up for me (:

[vvbandeira]

@vvbandeira do you understand the scan's error SyntaxWarning: invalid escape sequence '\('? I've never seen that before and there is no recent change.

I think it might be missing the r marker in the strings. I will do some testing and push a PR. But there's an exception to be made because the matching is being done with \dlp which matches 4Lp in the sha256.