Due to a recent Windows update from Microsoft®, the Nios® II build flow using Windows Subsytem for Linux (WSL) is presenting issues during project compilation and download.
The failure has been identified in computers running Windows 10 Version 1903 and later. The failure is not presented in Windows 10 Version 1809 or earlier.
Some of the error messages include:
nios2-elf-gcc.exe: error: CreateProcess: No such file or directory
nios2-elf-g++.exe: error: missing argument to '-msys-lib='
wslpath: /...........elf.srec: No such file or directory