# comment line
a = 111
b = 222
c = xx
d = $(d,undefined)
# comment line
a = aaa
b = bbb
c = ccc
d = $(d,undefined)
# comment line
a = AA
b = BB
c = xx
d = $(d,undefined)
# comment line
a = aaa
b = bbb
c = yy
d = $(d,undefined)
