From 916e614b7fdcb1ba4b7ce77868e84818b1373494 Mon Sep 17 00:00:00 2001 From: Samuel Martin Date: Mon, 17 Oct 2016 23:05:42 +0200 Subject: [PATCH] core: reorder top-level Makefile and document things This change only moves things around and comments what is done in the top-level Makefile file, in order to prepare the next changes. Note that moving the definition of $(O) before or after re-entering make does not change anything on the buildroot behavior. This change also renames the variable UMASK to REQ_UMASK. Cc: Arnout Vandecappelle (Essensium/Mind) Signed-off-by: Samuel Martin Acked-by: Arnout Vandecappelle (Essensium/Mind) Signed-off-by: Thomas Petazzoni --- Makefile | 59 ++++++++++++++++++++++++++++++++------------------------ 1 file changed, 34 insertions(+), 25 deletions(-) diff --git a/Makefile b/Makefile index 2c0ac231fe..717b2db92f 100644 --- a/Makefile +++ b/Makefile @@ -29,16 +29,46 @@ SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \ else if [ -x /bin/bash ]; then echo /bin/bash; \ else echo sh; fi; fi) -# Trick for always running with a fixed umask -UMASK = 0022 -ifneq ($(shell umask),$(UMASK)) +# Set O variable if not already done on the command line; +# or avoid confusing packages that can use the O= syntax for out-of-tree +# build by preventing it from being forwarded to sub-make calls. +ifneq ("$(origin O)", "command line") +O := output +else +# Other packages might also support Linux-style out of tree builds +# with the O= syntax (E.G. BusyBox does). As make automatically +# forwards command line variable definitions those packages get very +# confused. Fix this by telling make to not do so. +MAKEOVERRIDES := +# Strangely enough O is still passed to submakes with MAKEOVERRIDES +# (with make 3.81 atleast), the only thing that changes is the output +# of the origin function (command line -> environment). +# Unfortunately some packages don't look at origin (E.G. uClibc 0.9.31+) +# To really make O go away, we have to override it. +override O := $(O) +endif + +# Check if the current Buildroot execution meets all the pre-requisites. +# If they are not met, Buildroot will actually do its job in a sub-make meeting +# its pre-requisites, which is: +# 1- Permissive enough umask: +# Wrong or too restrictive umask will prevent Buildroot and packages from +# creating files and directories. + +REQ_UMASK = 0022 + +# we need to pass O= everywhere we call back into the toplevel makefile +EXTRAMAKEARGS = O=$(O) + +# Check Buildroot execution pre-requisites here. +ifneq ($(shell umask),$(REQ_UMASK)) .PHONY: _all $(MAKECMDGOALS) $(MAKECMDGOALS): _all @: _all: - @umask $(UMASK) && $(MAKE) --no-print-directory $(MAKECMDGOALS) + @umask $(REQ_UMASK) && $(MAKE) --no-print-directory $(MAKECMDGOALS) else # umask @@ -109,27 +139,6 @@ endif # Include some helper macros and variables include support/misc/utils.mk -# Set O variable if not already done on the command line; -# or avoid confusing packages that can use the O= syntax for out-of-tree -# build by preventing it from being forwarded to sub-make calls. -ifneq ("$(origin O)", "command line") -O := output -else -# other packages might also support Linux-style out of tree builds -# with the O= syntax (E.G. BusyBox does). As make automatically -# forwards command line variable definitions those packages get very -# confused. Fix this by telling make to not do so -MAKEOVERRIDES = -# strangely enough O is still passed to submakes with MAKEOVERRIDES -# (with make 3.81 atleast), the only thing that changes is the output -# of the origin function (command line -> environment). -# Unfortunately some packages don't look at origin (E.G. uClibc 0.9.31+) -# To really make O go away, we have to override it. -override O := $(O) -# we need to pass O= everywhere we call back into the toplevel makefile -EXTRAMAKEARGS = O=$(O) -endif - # Set variables related to in-tree or out-of-tree build. ifeq ($(O),output) CONFIG_DIR := $(TOPDIR) -- 2.30.2