Open Source Computing

Week 5

Week of February 12

Immich is switching from the MIT license to AGPL (that is quite a jump)

https://github.com/immich-app/immich/discussions/7023

Immich is a "self-hosted backup solution for photos and videos on mobile devices"

Vaultwarden switches to AGPL3: www.reddit.com/r/selfhosted/comments/110t8ni/vaultwarden_relicenses_to_agplv3. Vaultwarden is a fork rewritten in Rust of Bitwarden, which is a password manager. The AGPL3 makes a lot of sense here: end users have a legitimate need to see the code.

Running the Simple-Calculator

• original version in ~/412/projects/SimpleJavaCalculator: runs under netbeans, or with javac/java with package lines commented out
• new version in ~/412/now/calculator/SimpleJavaCalculator: netbeans can't find main class, command-line: UI construction fails

Demo of git

Wednesday

Git is a lot like marriage.

First you commit.

Then you merge.

And then you resolve conflicts. Over and over again.

Each team should select a reporter who will email me every week (generally on Fridays) to let me know your team's progress. You don't have to make progress, but you do have to report. At the moment, your main issue is selecting a project.

Continue with licenses.html at Ethical Licenses

Clang

Why did Apple create the Clang compiler, and switch from gcc?

In 1989 NeXT computer apparently added support for Objective-C to gcc, and distributed the binaries but never released the source. But this isn't the whole story: Clang is a front-end that is part of the LLVM open-source compiler project, which is licensed under the Apache license.

Even that isn't the whole story: while at UIUC, Chris Lattner did major development work on the LLVM compiler collection, and wrote his PhD thesis about it. After he got his PhD, Apple hired him to turn LLVM from a research compiler to a robust production compiler. And the source is still open.

One issue is that, back when gcc was first developed, compilers were strictly black boxes, that converted your source code to object code. But this is no longer really true: most IDSs have extensive hooks into their compiler. This way they can show compiler error messages tied to line numbers, and show syntax errors before compilation (because the parser runs on your source as you type). Clang also supports code-analysis plugins; under the Apache license, such plugins can remain proprietary. Could the plugin issue be the real reason for Clang? Clang also has internal structural features that make it easier to tie late-compilation and even run-time issues back to a specific source location.