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