#!/bin/bash

# ideone boilerplate: run in temp dir
t=$(mktemp -d -t ideone.XXXXXXXX) || exit
trap 'rm -rf "$t"' ERR EXIT
cd "$t"

tr _ '\011' <<\: >Makefile
poo := ick
bar := quux
baz := foo
export baz
.PHONY: all
all:
_nl -ba Makefile
_env | grep -e ^poo -e ^bar -e ^baz
export poo
:

make