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by StefanKarpinski 3738 days ago
> Julia crashes all the time with segmentation faults, sorry, the quality of Julia is super low. I would not use it for anything serious.

I've seen a lot of Julia used in real world scenarios at companies and this is a pretty surprising claim. Segfaults are very rare – much rarer than in code written in C or C++. You may either have a messed up build of Julia or you could be using packages that call C libraries and do so incorrectly – that would certainly cause segfaults.
1 comments
fredmorcos 3738 days ago
Sorry for not being clear on this. I was not talking about Julia code crashing. What I meant was when playing around with it, the julia binary would segfault here and there.

echo "print(3)" > boot.jl

julia --compile=all -O --inline=yes --check-bounds=no --output-o foo.o

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nickpsecurity 3738 days ago
Stefan can tell me if my hunch is right but check-bounds=no might turn off protections against out-of-bounds, memory access. If so, then that command is straight up telling it to segfault.
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StefanKarpinski 3738 days ago
That's true, but it shouldn't segfault unless you do an out-of-bounds memory access, which this code isn't doing.

However, there seems to be a misunderstanding about how --compile=all (an experimental feature on the development branch of Julia) works. You can't run an impure operation like print during compilation. In the future, we may have a `julia-compile` command that translates a given Julia program into a binary equivalent, which seems to be what @fredmorcos expects, but that's not how the --compile=all flag works.

If you use Julia in the normal manner like you would Python, it's very reliable and stable. If you use experimental features and use them wrong, you can get segfaults. See these posts for more information about and some examples of using the Julia's experimental static compilation features:

http://juliacomputing.com/blog/2016/02/09/static-julia.html

http://juliacomputing.com/blog/2016/03/10/j2c-announcement.h...

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nickpsecurity 3738 days ago
That makes a lot of sense. Yeah, you should consider renaming it to something more clear. Maybe even change it into several commands with better names. Your docs frame the issue as whether it allows dynamic/JIT stuff or not. So, static-only, allow-dynamic, or allow-jit come to mind.
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StefanKarpinski 3738 days ago
> Maybe even change it into several commands with better names.

That's what I've been pushing for – I don't think it make sense to continue to have all these compilation-related flags baked into the interactive `julia` command.

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