Emacs master on builds with full bootstrap on Windows

[Andy Moreton]

HI,

Emacs master fails to build for the last day or so for 64bit mingw64 on
Windows. A full bootstrap succeeds, but any subsequent builds fail with:

Dumping from C:/emacs/git/emacs/master/obj-mingw64-x86_64/src/temacs.exe
          to C:/emacs/git/emacs/master/obj-mingw64-x86_64/src/emacs.exe
mv -f emacs.exe bootstrap-emacs.exe
make -C ../lisp compile-first EMACS="../src/bootstrap-emacs.exe"
make[2]: Entering directory '/c/emacs/git/emacs/master/obj-mingw64-x86_64/lisp'
  GEN      ../../lisp/mh-e/mh-loaddefs.el
Symbol's function definition is void: w32-convert-standard-filename
make[2]: *** [Makefile:394: ../../lisp/mh-e/mh-loaddefs.el] Error 127
make[2]: Leaving directory '/c/emacs/git/emacs/master/obj-mingw64-x86_64/lisp'
make[1]: *** [Makefile:755: bootstrap-emacs.exe] Error 2
make[1]: Leaving directory '/c/emacs/git/emacs/master/obj-mingw64-x86_64/src'
make: *** [Makefile:414: src] Error 2

git rev-parse master
aaf86f30f709b22e9bae8cdb23ec89342dcaa55f

Running a non-parallel build does not help - only a full bootstrap
succeeds.

    AndyM