1foo = FOO
 2bar = BAR
 3dp := $$(
 4$(dp)foo := PASS_UNMATCHED
 5FOO1BAR := PASS_MATCHED
 6baz = 0$($(foo)1$(bar)2
 7# baz will be 0PASS_UNMATCHED, 1$(bar)2 will be discarded??
 8baz2 = 0$($(foo)1$(bar))2
 9# baz2 will be 0PASS_MATCHED2.
10
11test:
12	echo "$(baz)"
13	echo "$(baz2)"