That's a typo, should be make -C src/ bootstrap-emacs.exe 

On Sun, Dec 20, 2020, 02:38 Michael Albinus <michael.albinus@gmx.de> wrote:
=?UTF-8?Q?Li=C4=81u@debbugs.gnu.org, _?= Kiong-Gē 廖宮毅
<gongyi.liao@gmail.com> writes:

> a segmentation error at make -C src/bootstramp-emacs.exe:
                                           ^^^^^
Wow, didn't know aqbout :-)

SCNR, Michael.