Hi, I ran into a very similar problem last week when compiling the preloader for a Cyclone V on Ubuntu 17.04. I got “Command not found” for arm-altera-eabi-gcc. The directory to arm-altera-eabi.gcc was in my path, and the file was present. Even when I was in that directory and tried to execute ./arm-atera-eabi-gcc, I received “Command not found”.
With some help, it was determined that the 32 bit loader, ld-linux.so.2 was missing. We figured it out by executing the “ldd” command against the arm-altera-eabi.gcc file (pipe the output to grep, searching for “not found”). Note: I was already in the directory where arm-altera-eabi-gcc was located, but the path can be specified in the command.
ldd arm-altera-eabi-gcc | grep “not found”
The ldd command finds shared libraries required by programs.
Went to the Ubuntu packages search page, searched contents of package for ld-linux.so.2. It is in libc6-i386 - downloaded and installed it with command:
sudo apt-get install libc6-i386
It fixed the problem.