Which behavior is expected of $(shell )

Hi,

Here is the Makefile:

KBUILD_OUTPUT =
defs := $(shell echo $$KBUILD_OUTPUT)
all:
         @echo "KBUILD_OUTPUT in shell is $(defs)"
         @echo "KBUILD_OUTPUT is $(KBUILD_OUTPUT)"


1.  For make version 4.3

$ KBUILD_OUTPUT=test make

KBUILD_OUTPUT in shell is test

KBUILD_OUTPUT is


2.  For make version 4.4

$ KBUILD_OUTPUT=test make

KBUILD_OUTPUT in shell is

KBUILD_OUTPUT is


Here is what the make manual says,

6.10 Variables from the Environment

- However, an explicit assignment in the makefile, or with a command 
argument, overrides the environment.

- Note this is not totally reliable; some makefiles set CFLAGS 
explicitly and therefore are not affected by the value in the environment.


I think the behavior of 4.4 is aligned with doc, if KBUILD_OUTPUT is 
explicit set in Makefile,   in $(shell) , it should also use the value 
set in Makefile, not still use

the value in shell environment like what 4.3  done. But I don't find 
which commit or bug ID is for fixing this issue,  so I send this mail to 
double check with the

exports at this. Thanks a lot.


Best regards

Changqing