Ubuntu 21: sudo apt install failed, causing by gcc-11-base unmet dependencies on libgfortran5 :(

Question

My sudo apt install encountered problem when trying to install OpenCV. It fails on package libgfortran5, which OpenCV and libopencv-dev needs. The output is

The following packages have unmet dependencies:
libgfortran5 : Depends: gcc-11-base (= 11-20210417-1ubuntu1) but 11.1.0-1ubuntu1~21.04 is to be installed
E: Unable to correct problems, you have held broken packages.

I tried to downgrade gcc-11-base to 11-20210417-1ubuntu1 with command sudo apt-get install gcc-11-base=11-20210417-1ubuntu1, but it will remove 2.6G of stuff, which I believe will crash the system. So, I didn't say yes to "You are about to do something potentially harmful."

Please let me know if you have encountered this issue before. Thanks a lot!

Logistics:

System: Ubuntu Desktop 21.04
Hardware: Raspberry Pi 4B (8Gb men) aarch64
Python: version 3.8.7 correctly installed (default)
I might have messed around with /etc/apt/sources.list since I needed to add some random repository to install python3.8 (according to some tutorials) [I highly suspect that this is causing the problem.]

Thanks a lot,

Terry

.

To answer community suggestions:

Thank you guys for your prompt suggestions.

I installed the Ubuntu 21.04 Desktop from this link https://ubuntu.com/download/raspberry-pi
Yes, I understand that this is a arm system, which x86 packages will fail on any raspberry pi. I simply want to install opencv on pi, the command I ran to do so is "sudo apt install libopencv-dev python3-opencv" as suggested here https://linuxize.com/post/how-to-install-opencv-on-ubuntu-20-04/
I tried that post, and it didn't solve the issue unfortunately (that's why I wrote this post). I don't have any hold packages. Aptitude did successfully install I think, but cv2 module cannot be found when I ran python
In my /etc/apt/sources.list, I have the following links. I highly think these are mal-configured. Any idea of fixing it? Thanks a lot!

deb http://us.archive.ubuntu.com/ubuntu/ hirsute main
deb http://us.archive.ubuntu.com/ubuntu/ hirsute universe
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute main universe multiverse

Also, when I installed python, I ran this command sudo add-apt-repository ppa:deadsnakes/ppa. Maybe this causes the issue?

Ubuntu 21? No such release. Ubuntu uses the year format for snap only releases, but you start with a sudo apt install which doesn't work on year format products. Please clarify your release. — guiverc, Jul 22 '21 at 03:16
If you look at https://packages.ubuntu.com/hirsute/libgfortran5 you'll note you have/are trying to install i386/amd64 packages it appears on what you say is an arm64 system. Do you understand what the architecture means? Correct your sources! — guiverc, Jul 22 '21 at 03:20
Does this answer your question? Unable to correct problems, you have held broken packages — guiverc, Jul 22 '21 at 03:20
Please provide details of exactly what you did to the software sources. The staff mind-reader is on break. — Organic Marble, Jul 22 '21 at 03:23
Please see my edited post, for I provide more info to your suggestions there. Thanks a lot! I really hope I can get this(OpenCV) working. — Terry W, Jul 23 '21 at 05:32

Ubuntu 21: sudo apt install failed, causing by gcc-11-base unmet dependencies on libgfortran5 :(

0 Answers0