* mtrace

  You need to build and install mtrace:
    git+ssh://amsterdam.csail.mit.edu/home/am6/mpdev/qemu.git -b mtrace

  #define MTRACE 1 in param.h
  $ make mscan.out

* Networking with lwIP

  $ git clone git://git.savannah.nongnu.org/lwip.git
  $ (cd lwip && git checkout DEVEL-1_4_1)
  $ make clean;make

* Copies of e1000 and e1000e manuals are in manuals/.  They were
  retrieved from:

  http://www.intel.com/products/ethernet/resource.htm#s1=Gigabit%20Ethernet&s2=all&s3=Manual

* qemu+gdb

  # In a terminal..
  $ make gdb

  # ..In a different terminal
  $ gdb o.qemu/kernel
  (gdb) target remote :1234
  (gdb) show arch
  The target architecture is set automatically (currently i386:x86-64)
  (gdb) set arch i386:x86-64:intel
  (gdb) show arch
  The target architecture is assumed to be i386:x86-64:intel
  (gdb) c

* Mac cross compiler gcc-4.6.2
  compiler without libstdc++
  download, make, make install gmp-5.0.4, mpfr-3.1.0, and mpc-0.9
  for mpfr and mpc: ./configure --with-gmp=/usr/local
  for gcc: 
  mkdir build
  cd build
  ../configure --target=x86_64-jos-elf  --with-gmp=/usr/local/ --with-mpfr=/usr/local --enable-languages=c,c++ --without-headers --disable-nls
  make all-gcc ; sudo make install-gcc

* clang 
  - Version 3.0 or greater is required to build xv6
  - http://llvm.org/docs/GettingStarted.html

  $ git clone http://llvm.org/git/llvm.git
  $ (cd llvm/tools && git clone http://llvm.org/git/clang.git)
  $ CC=gcc CXX=g++ ./configure --prefix=[PREFIX] \
    --enable-targets=x86_64 --enable-optimized
  $ CC=gcc CXX=g++ make && make install

* user-space version

  $ apt-get install libjemalloc-dev
  $ make HW=user
  $ ./o.user/utest
