Panics on misaligned struct fields on ARM 32 bit

[nkryuchkov]

Describe the bug
I got a nil pointer dereferencing runtime panic on RPi because of atomic.LoadUint64 on a struct field not aligned by 8 bytes. We need to think about a way how we can check and avoid such panics.

Environment information:

• Platform: ARM 32 bit

Steps to Reproduce
Steps to reproduce the behavior:

1. Call atomic.LoadUint64 on a struct field not aligned by 8 bytes.

Actual behavior
Calling atomic.LoadUint64 on a struct field not aligned by 8 bytes causes panic.

Expected behavior
Calling atomic.LoadUint64 on any struct field not aligned by 8 bytes doesn't cause panic.

Additional context
This is a well-known behavior. We need to create a way of checking if all struct fields are correctly aligned. This issue also affects the dmsg repository.

[nkryuchkov]

Adding ARM 32-bit builds to TravisCI may help to detect the panics.

[nkryuchkov]

Adding ARM32 builds to .travis.yml didn't help, TravisCI doesn't support them. Adding ARM64 works, however, doesn't help much as it behaves the same as AMD64, panics occur on ARM32 only. I tried to set up a Docker container with emulation of ARM32 using QEMU and with Golang for ARM32. However, it trows segfaults on almost all commands. And the speed doesn't look good.

The best option would be to wait until TravisCI supports ARM32 builds.