Install.sh script misdetects architecture on arm64 kernel with arm32 userspace

[nestukh]

Bug Report

Bug originally mentioned in #292 (comment)

A Vero 4K+ (by OSMC) is a Kodi box which has Debian with aarch64 (arm64) architecture. It's very versatile but it hasn't Xorg installed. It has its own debian repo apt.osmc.tv and uses the official http://ftp.debian.org/debian stretch main contrib non-free as well. Yes the stable version is still on Debian Stretch but it's very stable.
It can be accessed on the command line via ssh over Wi-Fi. The default user is named osmc, who has sudo privileges as well.

Current behavior

installing with the command
curl -fsSL https://raw.githubusercontent.com/arduino/arduino-cli/master/install.sh | sh
I obtain

Installing in /home/osmc/bin
ARCH=ARM64
OS=Linux
Using curl as download tool
TAG=0.13.0
CLI_DIST=arduino-cli_0.13.0_Linux_ARM64.tar.gz
Downloading https://downloads.arduino.cc/arduino-cli/arduino-cli_0.13.0_Linux_ARM64.tar.gz
main: line 204: /home/osmc/bin/arduino-cli: No such file or directory
Failed to install arduino-cli

But the binary /home/osmc/bin/arduino-cli exists, ergo it's made for the wrong arch, like it was happening in issue 307. I manually installed the arduino-cli binary from arduino-cli-152-PR307-linuxarm64.tar.bz2 found in a comment there and it works: the output of arduino-cli version with the 152-PR307 version is
arduino-cli Version: 152-PR307 Commit: 77d5613
and can run other subrutines as well.

I probably could install the 32 bit armhf architeture like suggested online in some places (like here), but it don't like to mess up things and hope for the best. Space is also limited.
It there is a clean solution that you know of, the avr-g++ binary from the main arduino installer has the same problem on this machine (issue 73 on toolchain-avr): running a normal command like arduino-cli compile --fqbn arduino:avr:uno Sketch01, I'm getting a classic error:

Error: build failed: fork/exec /home/osmc/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/avr-g++: no such file or directory
Error during build

avr-g++ exists but it's for the wrong arch for sure (it's typical behaviour with wrong arch binaries). But this problem cannot be solved removing the .arduino15 folder like suggested in many places.

[matthijskooijman]

I probably could install the 32 bit armhf architeture like suggested online in some places (like here)

As we figured out in arduino/toolchain-avr#73, the problem is actually reversed: You have a 32-bit userspace already, so should be using a 32-bit arduino-cli rather than a 64-bit arduino-cli.

I can't explain why the older PR307 version you linked, which is also 64-bit, does work, but I don't find it particularly interesting either, since I don't think the 64-bit version can be expected to work on your system.

So, the bug I see here is that the arduino-cli install.sh script misdetects your system as a 64-bit system, presumably because it is running a 64-bit kernel, even though the userspace is 32-bit. This is a bug, since the installer script should detect and install the right version, even on a more complicated system like this, I think. I'm not sure how easy this is to fix, though.

[umbynos]

we use uname to detect the architecture in the install script. Could you please run uname -a and tell us what is reporting?
To me it seems a strange setup to support