On Fri, 29 May 2020, Izumi Tsutsui wrote:
src/distrib/common/bootimage/Makefile.bootimage (included from Makefile.installimage) already has "USE_MBR?= no" line.
Makefile.installimage refers to it before including Makefile.bootimage and this test was causing make to throw an error:
https://nxr.netbsd.org/xref/src/distrib/common/bootimage/Makefile.installimage#41All other users (i386, amd64) of Makefile.installimage explicitly set USE_MBR=yes. That's why it wasn't an issue before now.
Cheers, Jared