Makefile variable initialization and export

Question

somevar := apple
export somevar
update := $(shell echo \"v=$$somevar\")

all:
    @echo $(update)

I was hoping to apple as output of command, however i

Answer 1

Running the makefile

foo:=apple
export foo
all:
        @echo ">"$(shell echo "$$foo")
        @echo ">""$$foo"

gives for me (with foo undefined in the environment)

$ make
>
>apple

$ make foo=bar
>
>apple

$ export foo=bar; make
>bar
>apple

$ export foo=bar; make foo=bar
>bar
>bar

Try using the quoted form (update := "v=$$somevar") and let the shell handle expansion when a command is run (you'll still need the export)