Re: Why MAKEFLAGS is set to `w' in sub directory?

[Paul Smith]

On Mon, 2016-03-14 at 18:13 +0900, Masato Asou wrote:
> Why MAKEFLAGS is set to `w' in sub directory?

Because that's how it's documented to work.  See "The '--print
-directory' Option" in the GNU make manual:

    Normally, you do not need to specify this option because ‘make’ does
    it for you: ‘-w’ is turned on automatically when you use the ‘-C’
    option, and in sub-makes.  make will not automatically turn on ‘-w’
    if you also use ‘-s’, which says to be silent, or if you use
    ‘--no-print-directory’ to explicitly disable it.