Raspberry Pi: First `rebuild switch` hangs on `gcc ... ruby`

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#1

Hello,

New to NixOS but been using RPis for a few years and have some experience with a handful of Linux distros.

I had nixos running on an RPi 3b for a couple weeks and decided to see what a “fresh reinstall” looked like, since my understanding is that one of the big advantages of nixos is reproducibility of a system based essentially just the configuration.nix.

  • backed up my full SD card just in case
  • copied /etc/nixos/*.nix to another computer
  • followed the NixOS on ARM instructions to download a fresh aarch64 build of 20.03 (seems to be passing)
  • verified the hash on the download
  • flashed this to my SD card
  • booted (seems fine)
  • start sshd and change root passwd
  • copy over my backed up *.nix
  • sudo nixos-rebuild switch test

Here, it hangs on a step that looks like gcc trying to compile ruby. I’ve let it run overnight, rebooted, even reflashed the SD card and tried again, every time it hangs here.

gcc -c -I. -I/nix/store/ay3n1j1gf2n3gyqrafwm38wp1m048wrm-ruby-2.6.6/include/ruby-2.6.0 -I/nix/store/ay3n1j1gf2n3gyqrafwm38wp1m048wrm-ruby-2.6.6/include/ruby-2.6.0/aarch64-linux -DRUBY_VERSION=26 -Iproto -DHAVE_CONFIG_H -DFEAT_GUI_GTK  -I/nix/store/jw03x2qw8mhag52xwr4xnqq6pdyjw1n2-glib-2.62.4-dev/include -I/nix/store/jw03x2qw8mhag52xwr4xnqq6pdyjw1n2-glib-2.62.4-dev/include/glib-2.0 -I/nix/store/q8w0nyhx2acvcgx7kkdfps0wmgvvz3dj-glib-2.62.4/lib/glib-2.0/include -I/nix/store/l5bx9mxi69zaydl6q79bb3lq5dvbd8n5-gtk+3-3.24.13-dev/include/gtk-3.0 -I/nix/store/wrn2xwn6hlzjrpnn8182bj77a21jmh0a-atk-2.34.1-dev/include/atk-1.0 -I/nix/store/l4q6142p28jjaicwfa70lwnxr26phal6-cairo-1.16.0-dev/include/cairo -I/nix/store/yld0m23fal83ysampmh09r4w5v9vk0s4-freetype-2.10.1-dev/include/freetype2 -I/nix/store/yld0m23fal83ysampmh09r4w5v9vk0s4-freetype-2.10.1-dev/include -I/nix/store/lkih64gvysch2lzzxbgzc0fd355ybm0z-gdk-pixbuf-2.40.0-dev/include/gdk-pixbuf-2.0 -I/nix/store/yks37jgp165c1nshh7awd58l67xja2cy-pango-1.44.7-dev/include/pango-1.0 -I/nix/store/ycjgh2pb91y89nij4z2jf5pycgrkr4ah-harfbuzz-2.6.4-dev/include/harfbuzz   -g -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1        -o objects/if_ruby.o if_ruby.c

What is going wrong? And should it be downloading from the aarch64 binary cache instead of compiling from source here?

Many thanks in advance!

#2

Huh, maybe I’m using the wrong image?

What’s the difference between these two:

?

I’m using the first one.

#3

I guess those two are just two names for the same image? I thought they may be different since the latter has an extra -aarch64 in the name, but the downloaded images seem to have the same naming scheme (just a different build number).

Tried both of these with no dice, also hangs on nixos-rebuild switch (or test).

#4

Working now, with no particularly interesting changes. ¯\_(ツ)_/¯

The only things I did differently:

  • Installed the 1943.de493bd7492 build, which didn’t work (hung at the same place as above)
  • Removed my /etc/nixos/*.nix files and instead used nixos-generate-config to get something generic
  • Ran sudo nixos-rebuild switch --upgrade, which worked
  • Reboot
  • Then the default boot target wouldn’t boot? Hung on boot screen at waiting for kernel or something like that
  • Ran sudo nixos-rebuild switch --upgrade, again, which worked
  • Reboot (with default boot target) which now worked for some reason
  • Reinstall my /etc/nixos/*.nix and remove /etc/nixos/hardware.nix (which I hadn’t used previously)
  • Ran sudo nixos-rebuild switch --upgrade, again, which worked this time (no hang at ruby)
  • Reboot

Everything is back to normal now. No idea why.