dnl Common configure.in fragment
AC_DEFUN([AM_BINUTILS_WARNINGS],[
-GCC_WARN_CFLAGS="-W -Wall -Wstrict-prototypes -Wmissing-prototypes"
+GCC_WARN_CFLAGS="-W -Wall -Wstrict-prototypes -Wmissing-prototypes -Wshadow"
AC_ARG_ENABLE(werror,
[ --enable-werror treat compile warnings as errors],