Minimum Boost Verson 1.83?

[noizfactory]

Hi John / devs,

I am trying to test some cortex updates for gaffer and I needed to rebuild the whole dependencies project. I only have access to Mac right now so while giving it a go, I noticed that the boost config points to 1.80 version but that gives me tons of outdated c++ function call errors since the target is c++17 (I'm on xcode 16.1). If I change the boost version to 1.83, then it seems to build correctly.

So, is the boost config in the project outdated? I also noticed that the config points to a dead boost download link and had to change that as well.

Cheers,
Sachin

[johnhaddon]

Yep, Boost 1.80 is correct, because we're currently still targeting VFXPlatform 2023. Murray recently fixed the download link in #272, so I'm surprised that isn't working for you. Perhaps you are building from main rather than 9_maintenance (you'll definitely want the latter).

I'm still on XCode 13, so I'm afraid i don't know anything about XCode 16, but we do build with C++17 on Linux and Windows without trouble.

[noizfactory]

Aah I see, thanks for the heads-up. I will try with the maintenance branch.

[noizfactory]

Thanks @johnhaddon, the dependencies project now builds correctly after I switched to the maintenance branch and also downgraded my Xcode to 13.4.1. Previously, I was also able to build it partially with Xcode 16.x and boost 1.83 but eventually it was failing at OpenImageIO project where it seemed to be explicitly looking for boost 1.8 (probably from one of the find cmake files) so I was stuck at that point. I should have asked your toolchain here first rather than struggling with testing different xcode versions :-)

If you don't mind me asking a few questions as it's been a while since I built the whole dependencies project.

1. I know that the build process writes a digest file in the buildDir which keeps a tab on what to skip when rebuilding and I can also build specific project if required. But how is the build.py figuring out the dependency order? I couldn't find that anywhere and I do remember there used to be a config for this years ago? I know each project has its own config.py with the dependencies of other projects but I wanted to find out how build.py builds the project in a specific order (when no project is specified).
2. How does one go about testing gaffer updates which also need cortex updates? I am just trying out some simple IECoreUSD stuff which means I need to rebuild cortex and then build gaffer again. But since cortex is also built as part of the dependencies project, what is the chain of operations that I need to follow? Do I do my cortex updates, build cortex by itself and then create a release package. Then I update the cortex project's config.py in the dependency project to point to the specific release package so that it picks it up and rebuilds it when building the dependency project? But wouldn't the cortex standalone project be already built by then? Seems a bit redundant? Or maybe I am misunderstanding some aspects.
3. Since building cortex also requires boost and its own dependencies, do I point those to the pre-built libs and includes in the dependency project?

Cheers,
Sachin

[noizfactory]

The build seems to fail at partio due to the patches. If I remove the patches for the source, it builds fine and moves ahead.

[johnhaddon]

How is the build.py figuring out the dependency order?

Each config.py file has a dependencies list - we make sure we build all dependencies before building a project.

How does one go about testing gaffer updates which also need cortex updates?

When I'm working on Cortex, I don't use the dependencies project - I just build Cortex directly against the Gaffer install I have already, and install over the top. When I have that work done, and merged into the Cortex repo, there are two avenues to updating the official Gaffer builds :

1. Build Gaffer against the new Cortex release packages (since they are built against GafferHQ/dependencies they contain all of that too). We use this whenever Cortex has changed but no other dependency has.
2. Update GafferHQ/dependencies with the new Cortex and release a new version. This is the proper way of doing it. Now we have CI builds automated for dependencies we should perhaps always go this route.

Since building cortex also requires boost and its own dependencies, do I point those to the pre-built libs and includes in the dependency project?

You could, or you could just point it at your Gaffer build.

[noizfactory]

Thank you for the pointers John, they are super helpful.

Just FYI, the dependencies build is now failing for OSL as it seems to expect minimum clang version 15.x as the llvm version is also 15.x and Xcode 13.x is quite old in comparison so its throwing up a lot of errors w.r.t. the styem headers and mismatched functions. I am not sure how the other projects built so far without this issue so I am going to give Xcode 15.x a try now.

It is certainly quite hairy to try building the whole dependencies project on osx and without a proper docker type container system!

[johnhaddon]

If your immediate goal is to work on Cortex, then perhaps it's worth starting from the prebuilt dependencies, and just building Cortex against them?