all: overrides=<> make -f varname-dot-makeoverrides.mk stage_1 VAR=value stage_1: overrides=< VAR> make -f varname-dot-makeoverrides.mk stage_2 stage_2: overrides=< VAR> make -f varname-dot-makeoverrides.mk stage_3 stage_3: overrides=< VAR> exit status 0