Replacement for GPL/GNU tools.

Major libraries:

  *  glibc: | musl libc] (could be relicensed)
  *  libstdc++: | libc++]
  *  libsupc++: | libcxxrt]
  *  libgcc: | compiler-rt]
  *  libgcc_s: | libunwind]

Basic utilities:

  *  binutils: | elftoolchain]
  *  groff: | mdocml]
  *  coreutils: | toybox]
  *  gcc/g++: | clang/llvm]

Other stuff (not such important, some of this should be in toybox at some point):

  *  make: | bmake] (not 100% compatible)
  *  bison: | byacc]
  *  bash: | mksh] (modern small ksh)
  *  gawk: | nawk] (one true awk)
  *  readline: | libedit]