NachOS 4.0 Setup on Ubuntu

Hackmd 好讀版：https://hackmd.io/@YUIN/HyR6haYkGx

This guide shows how to build and run NachOS 4.0 on Ubuntu.

Environment

Tested on Ubuntu 24.04.

1. Install dependencies

sudo apt update
sudo apt install g++ csh make wget vim g++-multilib gcc-multilib libc6-dev-i386 -y

2. Download files

mkdir -p ~/oslab
cd ~/oslab

wget -O nachos-4.0.tar.gz \
https://raw.githubusercontent.com/Yuin0329/NachOS-Setup/8deec2b725c1bcf115cc81fc5694bf478afdb154/nachos-4.0.tar.gz

wget -O mips-x86.linux-xgcc.tar.gz \
https://raw.githubusercontent.com/Yuin0329/NachOS-Setup/8deec2b725c1bcf115cc81fc5694bf478afdb154/mips-x86.linux-xgcc.tar.gz

3. Verify downloaded files

file nachos-4.0.tar.gz
file mips-x86.linux-xgcc.tar.gz

They should show gzip compressed data.

4. Extract files

tar -xzvf nachos-4.0.tar.gz
sudo tar -xzvf mips-x86.linux-xgcc.tar.gz -C /

Check the cross compiler:

ls /mips-x86.linux-xgcc

5. Edit code/test/Makefile

cd ~/oslab/nachos-4.0/code/test
vim Makefile

Set:

GCCDIR = /mips-x86.linux-xgcc/
CPP = /mips-x86.linux-xgcc/cpp0
CFLAGS = -G 0 -c $(INCDIR) -B/mips-x86.linux-xgcc/

6. Edit code/Makefile.common

cd ~/oslab/nachos-4.0/code
vim Makefile.common

Set:

CFLAGS = -m32 -g -Wall $(INCPATH) $(DEFINES) $(HOST) -DCHANGED
LDFLAGS = -m32

CPP=/lib/cpp
CC = g++ -m32 -Wno-deprecated
LD = g++ -m32 -Wno-deprecated
AS = as --32

7. Edit code/bin/Makefile

cd ~/oslab/nachos-4.0/code/bin
vim Makefile

Set:

CC=gcc -m32
CFLAGS=-m32 -I../lib -I../threads $(HOST)
LD=gcc -m32

8. Clean old build files (Optional / Troubleshooting)

If you already built NachOS with wrong settings, or make clean does not fully clean old files, remove old build files manually:

cd ~/oslab/nachos-4.0/code

find . -name "*.o" -delete
find . -name "nachos" -delete
find . -name "coff2noff" -delete
find . -name "swtch.s" -delete
find . -name "makedep" -delete
find . -name "eddep" -delete

cd test
rm -f *.o *.coff *.noff halt test1 test2 add createFile fileIO*

9. Build NachOS

cd ~/oslab/nachos-4.0/code
make

10. Run test

cd ~/oslab/nachos-4.0/code/userprog
./nachos -e ../test/test1

Expected output

You should see something similar to:

Total threads number is 1
Thread ../test/test1 is executing.
Print integer:9
Print integer:8
Print integer:7
Print integer:6
return value:0
Machine halting!

Notes

• If you already built with wrong settings, clean old build files before rebuilding.
• If test1 runs successfully, the setup is complete.