Posix build on Windows: parallel `make' broken

[Óscar Fuentes]

A few days ago I succesfully built Emacs on Windows using the MSYS build
with `make -j4'. Since, I updated MSYS to the latest package versions
available through mingw-get and updated Emacs sources too.

Now, `make -j4' hangs.

Starting from a pristine state (all generated files deleted, empty build
directory) `make -j4 bootstrap' hangs thus:

(/d/dev/emacs/autoconf is the build directory, source directory is
/d/dev/emacs/emacs)

make[1]: Entering directory `/d/dev/emacs/autoconf/lib'
test -z "" || rm -f
test -z "libgnu.a " || rm -f libgnu.a
rm -f *.o
test -z "core *.stackdump alloca.h alloca.h-t errno.h errno.h-t execinfo.h execi
nfo.h-t getopt.h getopt.h-t arg-nonnull.h arg-nonnull.h-t c++defs.h c++defs.h-t
warn-on-use.h warn-on-use.h-t stdalign.h stdalign.h-t stdarg.h stdarg.h-t stdboo
l.h stdbool.h-t stddef.h stddef.h-t stdint.h stdint.h-t " || rm -f core *.stackd
ump alloca.h alloca.h-t errno.h errno.h-t execinfo.h execinfo.h-t getopt.h getop
t.h-t arg-nonnull.h arg-nonnull.h-t c++defs.h c++defs.h-t warn-on-use.h warn-on-
use.h-t stdalign.h stdalign.h-t stdarg.h stdarg.h-t stdbool.h stdbool.h-t stddef
.h stddef.h-t stdint.h stdint.h-t
rm -f *.tab.c

It uses 100% of a CPU core, no changing memory usage. After 10 minutes I
try to kill it but doesn't respond to Control-C, so killed it with the
task manager and then the console shows:

make: *** [bootstrap-clean] Error 1
make: INTERNAL: Exiting with 1 jobserver tokens available; should be 4!


Also starting from a pristine state, a plain `make -j4' (without
`bootstrap') fails on a similar way on another place. `make -j1' works.

It seems that the latest MSYS/Make combo available from mingw-get is
broken when using parallel jobs.

make --version
GNU Make 3.81