[U-Boot] [PATCH v12 21/30] Makefile: Move SHELL setup to config.mk

[Benoît Thébaudeau]

make never uses the SHELL variable from the environment. Instead, it
uses /bin/sh, or the value assigned to the SHELL variable by the Makefile. This
makes the export of the SHELL variable useless for sub-makes (but still useful
for the environment of recipes). However, we want all makes to use the same
shell.

This patch fixes this issue by moving the SHELL variable setup and export to the
top config.mk, so that all Makefile-s including it use the same shell.

Since BASH is used by default, this makes it possible to use things
like 'echo -e ...' in sub-makes, which would otherwise fail e.g. with /bin/sh
symlinked to /bin/dash on Ubuntu.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau at advansee.com>
Reviewed-by: Tom Rini <trini at ti.com>
---
Changes in v12: None
Changes in v11: None
Changes in v10:
 - Rebase on current u-boot-arm/master.

Changes in v9: None
Changes in v8:
 - New patch.

Changes in v7: None
Changes in v6: None
Changes in v5: None
Changes in v4: None
Changes in v3: None
Changes in v2: None

 Makefile  |    7 +------
 config.mk |    7 +++++++
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/Makefile b/Makefile
index 8d0e2b8..caca851 100644
--- a/Makefile
+++ b/Makefile
@@ -46,12 +46,7 @@ HOSTARCH := $(shell uname -m | \
 HOSTOS := $(shell uname -s | tr '[:upper:]' '[:lower:]' | \
 	    sed -e 's/\(cygwin\).*/cygwin/')
 
-# Set shell to bash if possible, otherwise fall back to sh
-SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
-	else if [ -x /bin/bash ]; then echo /bin/bash; \
-	else echo sh; fi; fi)
-
-export	HOSTARCH HOSTOS SHELL
+export	HOSTARCH HOSTOS
 
 # Deal with colliding definitions from tcsh etc.
 VENDOR=
diff --git a/config.mk b/config.mk
index 4e6a19b..1fd109f 100644
--- a/config.mk
+++ b/config.mk
@@ -23,6 +23,13 @@
 
 #########################################################################
 
+# Set shell to bash if possible, otherwise fall back to sh
+SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
+	else if [ -x /bin/bash ]; then echo /bin/bash; \
+	else echo sh; fi; fi)
+
+export	SHELL
+
 ifeq ($(CURDIR),$(SRCTREE))
 dir :=
 else
-- 
1.7.10.4