Building or Testing on MacOS?

I’m new to rust development so maybe I’m missing something basic here, but I’m having trouble getting redox built on macOS (10.12.3 sierra) by following the steps in the readme.

I used rustup to get nightly installed:

rustc 1.16.0-nightly (df8debf6d 2017-01-25)

make output below:

make all
mkdir -p build/userspace
RUSTC="./rustc.sh" RUSTDOC="./rustdoc.sh" cargo rustc --manifest-path rust/src/libstd/Cargo.toml --features "panic-unwind" --target x86_64-unknown-redox --release -- -C codegen-units=`nproc` -L native=libc-artifacts/usr/lib -o build/userspace/libstd.rlib
/bin/sh: nproc: command not found
   Compiling compiler_builtins v0.0.0 (file:///Users/cdean/dev/foss/rust/redox-stuff/redox/rust/src/libcompiler_builtins)
   Compiling alloc_system v0.0.0 (file:///Users/cdean/dev/foss/rust/redox-stuff/redox/rust/src/liballoc_system)
   Compiling panic_abort v0.0.0 (file:///Users/cdean/dev/foss/rust/redox-stuff/redox/rust/src/libpanic_abort)
   Compiling unwind v0.0.0 (file:///Users/cdean/dev/foss/rust/redox-stuff/redox/rust/src/libunwind)
Build failed, waiting for other jobs to finish...
error: failed to run custom build command for `compiler_builtins v0.0.0 (file:///Users/cdean/dev/foss/rust/redox-stuff/redox/rust/src/libcompiler_builtins)`
process didn't exit successfully: `/Users/cdean/dev/foss/rust/redox-stuff/redox/rust/src/target/release/build/compiler_builtins-eae466b4ed0c523c/build-script-build` (exit code: 101)
--- stdout
TARGET = Some("x86_64-unknown-redox")
OPT_LEVEL = Some("2")
PROFILE = Some("release")
TARGET = Some("x86_64-unknown-redox")
debug=false opt-level=2
HOST = Some("x86_64-apple-darwin")
TARGET = Some("x86_64-unknown-redox")
TARGET = Some("x86_64-unknown-redox")
HOST = Some("x86_64-apple-darwin")
CC_x86_64-unknown-redox = None
CC_x86_64_unknown_redox = None
TARGET_CC = None
CC = Some("/Users/cdean/dev/foss/rust/redox-stuff/redox/libc-artifacts/gcc.sh")
TARGET = Some("x86_64-unknown-redox")
HOST = Some("x86_64-apple-darwin")
CFLAGS_x86_64-unknown-redox = None
CFLAGS_x86_64_unknown_redox = None
TARGET_CFLAGS = None
CFLAGS = Some("-fno-stack-protector -U_FORTIFY_SOURCE")
running: "/Users/cdean/dev/foss/rust/redox-stuff/redox/libc-artifacts/gcc.sh" "-O2" "-ffunction-sections" "-fdata-sections" "-fno-stack-protector" "-U_FORTIFY_SOURCE" "-m64" "-fPIC" "-fno-builtin" "-fvisibility=hidden" "-fomit-frame-pointer" "-ffreestanding" "-DVISIBILITY_HIDDEN" "-o" "/Users/cdean/dev/foss/rust/redox-stuff/redox/rust/src/target/x86_64-unknown-redox/release/build/compiler_builtins-e5736b878e16ba56/out/../compiler-rt/lib/builtins/absvdi2.o" "-c" "../compiler-rt/lib/builtins/absvdi2.c"
cargo:warning=/Users/cdean/dev/foss/rust/redox-stuff/redox/libc-artifacts/gcc.sh: line 15: x86_64-elf-gcc: command not found
ExitStatus(ExitStatus(32512))


command did not execute successfully, got: exit code: 127



--- stderr
thread 'main' panicked at 'explicit panic', /Users/cdean/.cargo/registry/src/github.com-1ecc6299db9ec823/gcc-0.3.40/src/lib.rs:1006
note: Run with `RUST_BACKTRACE=1` for a backtrace.

make: *** [build/userspace/libstd.rlib] Error 101

This should be fixed in the latest master.

Closed issue: https://github.com/redox-os/redox/issues/836