Re: The -e option confuses the $(origin ) ?

[Kaz Kylheku (gmake)]

On 2021-09-13 00:28, Masahiro Yamada wrote:
> masahiro@oscar:~/workspace/foo$ export FOO=2
> masahiro@oscar:~/workspace/foo$ make
> Makefile:1: the origin of FOO is: environment
> Makefile:2: the value of FOO is: 2
> make -e -f Makefile.sub1 FOO=1

Note that this FOO=1 will be exported to the environment. See the
GNU Make 4.3 manual, section 5.7.2 Communicating Variables to a 
Sub-make:

  "Except by explicit request, make exports a variable only if it is
   either defined in the environment initially or set on the command
   line, and if its name consists only of letters, numbers, and 
underscores."

> make[1]: Entering directory '/home/masahiro/workspace/foo'
> Makefile.sub1:1: the origin of FOO is: command line
> Makefile.sub1:2: the value of FOO is: 1
> make -f Makefile.sub2
> make[2]: Entering directory '/home/masahiro/workspace/foo'
> Makefile.sub2:1: the origin of FOO is: environment
> Makefile.sub2:2: the value of FOO is: 1

Here, we are seeing the value of FOO from the environment,
as exported by make -e -f Makefile.sub1 FOO=1.

(Since your makefiles do not define FOO themselves, the
effect of -e is not being demonstrated.)