Cross-Compiling

Crosscompiler generates code for alien CPU
Often needs special compiler options

  $ target=arm-unknown-linux-gnu
  $ xcflags="-mcpu=arm7 -D__ARM7__"
  $ PATH=/opt/$target/gcc-2.95.3-glibc-2.1.3/bin:$PATH
  $ $target-gcc $xcflags hello.c

Good Makefiles let you cross-compile like this:
  $ make CC=$target-gcc EXTRA_CFLAGS=$xcflags
but read the Makefile to see what variables to set