build: fix that defaultenv is always rebuilt
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From fcffd01
Mon Sep 17 00:00:00 2001
From: Sam Ravnborg <sam@ravnborg.org>
Date: Tue, 26 Dec 2017 16:47:16 +0100
Subject: [PATCH 1/4] build: fix that defaultenv is always rebuilt
Using following pattern:
target: prerequisite FORCE
$(call cmd,foo)
is almost always wrong. Due to FORCE target will be rebuilt
using cmd_foo no mater the timestamps.
The following pattern:
target: prerequisite FORCE
$(call if_changed,foo)
Will call cmd_foo only if:
- target is not updated
- or command to built target has changed
But to make this work target must be added to the
list af targets built.
This can be done by assigning target to extra-y or targets.
Use the latter pattern for defaultenv to avoid rebuilding
the environmentt for each build.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Sam Ravnborg
authored
on 26 Dec 2017
Sascha Hauer
committed
on 5 Jan 2018