How to run a QT5 program compiled for i386 on ubuntu 22.04.1

Question

I have an old program compiled for an ubuntu 16.04 i386, I need to run it or recompile for i386 architecture in my new pc (change 32 to 64 bit is quite complicated in this code". I have an ubuntu 22.04.1 but I dont know how to run 32 bit program on 64 bit ubuntu

Answer 1

First

sudo dpkg --add-architecture i386 
sudo apt-get update
sudo apt-get install libc6:i386 libstdc++6:i386

This allow my system to recognize which libraries the program needs. Then, know libs needed.

ldd your_program_name

I needed a lot of Qt libs so I installed.

sudo apt-get install qtbase5-dev:i386 qtmultimedia5-dev:i386

That is all that I needed.