The MIT has created xv6: an operating system for learning purpose
This works better and takes less time to create a working environnement for xv6 on Mac Os X, than the recommandations proposed on Tools used in 6.828 simply run this
port install i386-elf-gcc port install qemu
And change the Makefile like this:
-#TOOLPREFIX = i386-jos-elf- +TOOLPREFIX = i386-elf- -#QEMU = +QEMU = /opt/local/bin/qemu-system-i386 -CC = $(TOOLPREFIX)gcc +CC = $(TOOLPREFIX)gcc-4.3.2
Here is a working gdb binary simply bunzip2 it then invoke it from the xv6 directory souce tree, (tested on osx Lion).
make qemu will compile and run xv6 in qemu
make qemu-dbg will run xv6 in debug mode, run gdb-target-i386-elf and c for continue
Enjoy, thanks MIT.