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Latest blog posts

Early access: zcov

I am excited to announce my latest project, under the name zcov. It is a program for interpreting and appreciating coverage, with the goal of being the only tool you need for working with compiler instrumented coverage. It is still under development, but I have already been able to use it to understand and explain subtle program interactions, the path coverage view being particularly powerful. Planned features include MC/DC explainer, a way to explore the structure of a conditional expression and how the terms interact and mask, rich flow graph annotations, function search and filtering, path search and filtering, and HTML reports, plus a long list of quality of life features.

Bug hunt: Independent functions crashing gcov

NASA reported an odd crash in gcov, and I found it interesting and deep enough to warrant describing the root cause and the path it took me on. The actual crash itself was quickly found with gdb; reading the block.locations.lines when printing the source lines of a path when the array was empty (with size()-1, even!). A fix would be to not do that e.g. by guarding the access, but the question is why the array is empty in the first place.

Trip report: NDC Techtown 2024

This year’s Techtown conference in Kongsberg is through, and I wanted to do a trip report of sorts. There were ~400 attendees, the highest attendance yet, and an all-around fantastic atmosphere. I learnt a lot and had the privilege of striking conversations with many brilliant people, on diverse topics such as language design, compiler development, compiler features, embedded constraints, programming techniques, and I am already excited for next year. The programme was superb and I cannot think of a single slot where which talk to attend was an obvious choice.