Bazel is definitely buggy. One of the silliest ones is this one (and as far as this one goes, I do not understand how this issue exists when Blaze has been used in Google for such a long itme): https://github.com/bazelbuild/bazel/issues/9419
I've even had to clean --expunge and clear my disk cache to fix some build errors before. Bazel paints a rosy picture of the world, but the real world is messy, and Bazel builds aren't as reproducible as it makes you want to think. (Which BTW is one thing that's had me asking so many questions about Nix.) At least the fact that it does not track changes outside the workspace means you can update your system compilers (or Python, or whatever) and end up with build outputs that will not be reproduced from scratch.
It takes a lot of time to track the issues down, so I don't necessarily know what goes wrong every time; these are just two issues I remember off the top of my head. But if you haven't run into bugs with Bazel then you haven't used it seriously enough.
And then there's the Python support which is even more half-baked right now. Their own comments readily mention that the Python support is not idiomatic. (Not just in terms of syntax, but some of it goes against Bazel's underlying design.)
Of course I say this with the full realization that "fixing" these things can be a huge undertaking (up to and including hooking the compiler programs manually), but that doesn't mean they're not bugs.
As far as bazel bugs, it's safe to say that if you stick to the ways that Google uses blaze, then you are unlikely to run into bugs. E.g. Google doesn't run blaze on windows or use system toolchains, so it makes some sense that those are where the issues are. Unfortunately, Google also uses their own rules, so the rule quality for open source rules varies somewhat since they haven't all been battle tested in the same way. blaze and the Google codebase have also co-evolved for like 15 years to work nicely together, whereas anything adopting bazel today might be an awkward 3rd wheel for a while.
Yeah, I've figured as much in hindsight. It'd have been nice if they were more forthcoming about this than leaving it as a surprise for everyone to figure out (including, now, for the parent to whom I replied).
For a long time, Python3 support was advertised and there were lots of Python3 flags, but it was patently broken and there were many tickets that acknowledged as much. Allegedly that has changed now, but my experience was so bad I ran from it.
One of the more fundamental bugs is this one: https://github.com/bazelbuild/bazel/issues/4558
I've even had to clean --expunge and clear my disk cache to fix some build errors before. Bazel paints a rosy picture of the world, but the real world is messy, and Bazel builds aren't as reproducible as it makes you want to think. (Which BTW is one thing that's had me asking so many questions about Nix.) At least the fact that it does not track changes outside the workspace means you can update your system compilers (or Python, or whatever) and end up with build outputs that will not be reproduced from scratch.
It takes a lot of time to track the issues down, so I don't necessarily know what goes wrong every time; these are just two issues I remember off the top of my head. But if you haven't run into bugs with Bazel then you haven't used it seriously enough.
And then there's the Python support which is even more half-baked right now. Their own comments readily mention that the Python support is not idiomatic. (Not just in terms of syntax, but some of it goes against Bazel's underlying design.)
Of course I say this with the full realization that "fixing" these things can be a huge undertaking (up to and including hooking the compiler programs manually), but that doesn't mean they're not bugs.