On Mon, Nov 23, 2015 at 9:57 AM, Paul Smith <psm...@gnu.org> wrote: > Well, make doesn't know anything about backticks and doesn't ever do > anything special with them, so the answer is always "no, the command > inside the backticks is not executed when the variable is assigned".
I stand corrected. Here's a little demo of the interaction of backticks vs. $(shell ) and = vs := $ cat Makefile; make FOO1 = `date; sleep 1` FOO2 := `date; sleep 1` FOO3 = $(shell date; sleep 1) FOO4 := $(shell date; sleep 1) all: @echo FOO1 is $(FOO1) @echo FOO1 is $(FOO1) @echo FOO2 is $(FOO2) @echo FOO2 is $(FOO2) @echo FOO3 is $(FOO3) @echo FOO3 is $(FOO3) @echo FOO4 is $(FOO4) @echo FOO4 is $(FOO4) FOO1 is Mon Nov 23 10:21:12 PST 2015 FOO1 is Mon Nov 23 10:21:13 PST 2015 FOO2 is Mon Nov 23 10:21:14 PST 2015 FOO2 is Mon Nov 23 10:21:15 PST 2015 FOO3 is Mon Nov 23 10:21:10 PST 2015 FOO3 is Mon Nov 23 10:21:11 PST 2015 FOO4 is Mon Nov 23 10:21:09 PST 2015 FOO4 is Mon Nov 23 10:21:09 PST 2015 $(shell ...) is executed when the rule body is parsed `` is executed by the final shell _______________________________________________ Help-make mailing list Help-make@gnu.org https://lists.gnu.org/mailman/listinfo/help-make
