Fix alignment issues (and a test-only buffer overflow)

[saethlin]

Fixes #77

I ran this to find all the issues fixed here:

RUSTDOCFLAGS=-Zsanitizer=address ASAN_OPTIONS=detect_leaks=0 RUSTFLAGS=-Zsanitizer=address cargo +nightly test --target=x86_64-unknown-linux-gnu

ASan is still grumpy because JitMemory leaks the contents allocation. This is probably fine in practice I think because there won't be more than one JIT in a process? But if you want you could also add a Drop impl.

It would probably be good to use the above invocation when doing stuff in CI, but I'm awful with GitHub actions so I'll leave that to you if you want to do it.

[qmonnet]

Looks great, thanks a ton for fixing these!

[qmonnet]

ASan is still grumpy because JitMemory leaks the contents allocation.

How do you observe these? I don't see any remaining complaints when running the command you provided.

This is probably fine in practice I think because there won't be more than one JIT in a process? But if you want you could also add a Drop impl.

Yes, at the moment there would be only one, I haven't looked at multithreading for rbpf at this stage. I guess I could look into the Drop in the future.

It would probably be good to use the above invocation when doing stuff in CI, but I'm awful with GitHub actions so I'll leave that to you if you want to do it.

Sounds good, and it's alright, I should be able to handle that when I can find a moment for it. Thanks!

[saethlin]

How do you observe these? I don't see any remaining complaints when running the command you provided.

The command I provided sets ASAN_OPTIONS=detect_leaks=0 so it turns off leak reports. Delete that from the command and you should see complaints about leaks.

[qmonnet]

Fixed the memory leak and added flags to CI in #82, thanks again.