It did not go well 
Processing triggers for libgdk-pixbuf2.0-0:i386 (2.40.0+dfsg-3ubuntu0.2) ...
/var/lib/dpkg/info/libgdk-pixbuf2.0-0:i386.postinst: 16: /usr/lib/i386-linux-gnu/gdk-pixbuf-2.0/gdk-pixbuf-query-loaders: Exec format error
E: Could not configure 'libc6:i386'.
E: Could not perform immediate configuration on 'libgcc-s1:i386'. Please see man 5 apt.conf under APT::Immediate-Configure for details. (2)
/usr/bin/wine: 40: exec: /usr/lib/wine/wine: Exec format error
/usr/bin/wine: 40: exec: /usr/lib/wine/wine: Exec format error
/usr/bin/wine: 40: exec: /usr/lib/wine/wine: Exec format error
make[1]: *** [M
I symlinked wine64 to /usr/lib/wine/wine and re-ran it, and got to the same place you did
JULIA usr/lib/julia/sys-o.a
Generating REPL precompile statements... 40/40
Executing precompile statements... 1923/1963
Precompilation complete. Summary:
Total ------- 368.793083 seconds
Generation -- 298.478811 seconds 80.934%
Execution --- 70.314272 seconds 19.066%
make is still running
32720 tty1 S 0:00 make -s -C /home/matt/julia-win32 -f sysimage.mk sysimg-release
87 tty1 S 0:00 /bin/sh -c printf ' %b %b\n' "\033[32;1m"JULIA"\033[0m" "\033[37;1m"usr/lib/julia/sys-o.a"\033[0m"; cd /home/matt/julia-win32/base && if ! JULIA_BINDIR=`wine winepath.exe -w /home/matt/julia-win32/usr/bin` WINEPATH="`wine winepath.exe -w /home/matt/julia-win32/usr/bin`;$WINEPATH" JULIA_NUM_THREADS=1 wine /home/matt/julia-win32/usr/bin/julia.exe -O3 -C "native" --output-o `wine winepath.exe -w /home/matt/julia-win32/usr/lib/julia/sys-o.a`.tmp --startup-file=no --warn-overwrite=yes --sysimage `wine winepath.exe -w /home/matt/julia-win32/usr/lib/julia/sys.ji` `wine winepath.exe -w /home/matt/julia-win32/contrib/generate_precompile.jl` 1; then echo '*** This error is usually fixed by running `make clean`. If the error persists, try `make cleanall`. ***'; false; fi
129 tty1 R 13:55 /home/matt/julia-win32/usr/bin/julia.exe -O3 -C native --output-o Z:\home\matt\julia-win32\usr\lib\julia\sys-o.a.tmp --startup-file=no --warn-overwrite=yes --sysimage Z:\home\matt\julia-win32\usr\lib\julia\sys.ji Z:\home\matt\julia-win32\contrib\generate_precompile.jl 1
but it is an instance of julia itself which is consuming ~100% CPU (this is the glances process monitor)
CPU% MEM% VIRT RES PID USER TIME+ THR NI S R/s W/s Command
95.9 25.6 2.70G 2.03G 129 matt 14:54 1 0 R ? ? /home/matt/julia-win32/usr/bin/julia.exe -O3 -C native --output-o Z:\home\matt\julia-win32\usr\lib\julia\sys-o.a.tmp --startup-file=no --warn-overwrite=yes --sys
oh, it finished after about an hour
I shall make the binary tomorrow