make qemu/virtualbox fails on macOS 10.14.6

I agree that I have searched opened and closed issues to prevent duplicates.

Description

I cloned redox and ran ./bootstrap.sh -d and make all following the directions here: https://doc.redox-os.org/book/getting_started/preparing_the_build.html. That all went through without a hitch but I can't get redox to start in a VM. I've tried

make qemu
make qemu kvm=no
make qemu iommu=no
make virtualbox but all of them fail with

redox $ make qemu
...
x86_64-unknown-redox-gcc -nostdlib -shared -Wl,--allow-multiple-definition -Wl,--whole-archive "target/x86_64-unknown-redox"/release/librelibc.a "target/x86_64-unknown-redox"/pthreads-emb/libpthread.a "target/x86_64-unknown-redox"/openlibm/libopenlibm.a -Wl,--no-whole-archive -o "target/x86_64-unknown-redox"/release/libc.so
for lib in "target/x86_64-unknown-redox"/release/librelibc.a "target/x86_64-unknown-redox"/pthreads-emb/libpthread.a "target/x86_64-unknown-redox"/openlibm/libopenlibm.a; do\
		echo "addlib $lib" >> ""target/x86_64-unknown-redox"/release/libc.a.mri"; \
	done
echo "save" >> ""target/x86_64-unknown-redox"/release/libc.a.mri"
echo "end" >> ""target/x86_64-unknown-redox"/release/libc.a.mri"
ar -M < ""target/x86_64-unknown-redox"/release/libc.a.mri"
usage:  ar -d [-TLsv] archive file ...
	ar -m [-TLsv] archive file ...
	ar -m [-abiTLsv] position archive file ...
	ar -p [-TLsv] archive [file ...]
	ar -q [-cTLsv] archive file ...
	ar -r [-cuTLsv] archive file ...
	ar -r [-abciuTLsv] position archive file ...
	ar -t [-TLsv] archive [file ...]
	ar -x [-ouTLsv] archive [file ...]
make[1]: *** ["target/x86_64-unknown-redox"/release/libc.a] Error 1
make[1]: *** Waiting for unfinished jobs....
make: *** [prefix/x86_64-unknown-redox/relibc-freestanding-install] Error 2
redox $

Environment info

Redox OS Release: n/a

Operating system: Replace me
uname -a: Darwin Samuels-MacBook-Pro-2.local 18.7.0 Darwin Kernel Version 18.7.0: Thu Jun 20 18:42:21 PDT 2019; root:xnu-4903.270.47~4/RELEASE_X86_64 x86_64
rustc -V: rustc 1.41.0-nightly (412f43ac5 2019-11-24)
git rev-parse HEAD: 2909452c82091e360ef8dd2b72d12f7f7e83a864

Steps to reproduce

Clone redox at 2909452c on a macOS 10.14.6 machine.
Run ./bootstrap.sh -d
Run make all
Try make qemu

Behavior

Expected behavior: Redox to start

Actual behavior: It doesn't work