diff --git a/build_sysroot/Cargo.toml b/build_sysroot/Cargo.toml
index c5bf0705c19..1039f4613ef 100644
--- a/build_sysroot/Cargo.toml
+++ b/build_sysroot/Cargo.toml
@@ -8,12 +8,14 @@ core = { path = "./sysroot_src/src/libcore" }
 compiler_builtins = "0.1"
 alloc = { path = "./sysroot_src/src/liballoc" }
 std = { path = "./sysroot_src/src/libstd", features = ["panic_unwind"] }
+test = { path = "./sysroot_src/src/libtest" }
 
 alloc_system = { path = "./alloc_system" }
 
 [patch.crates-io]
 rustc-std-workspace-core = { path = "./sysroot_src/src/tools/rustc-std-workspace-core" }
-rustc-std-workspace-alloc = { path = "./rustc-std-workspace-alloc" }
+rustc-std-workspace-alloc = { path = "./sysroot_src/src/tools/rustc-std-workspace-alloc" }
+rustc-std-workspace-std = { path = "./sysroot_src/src/tools/rustc-std-workspace-std" }
 
 [profile.dev]
 # FIXME On macOS statics and promoted constants have the wrong alignment. This causes a debug
diff --git a/build_sysroot/build_sysroot.sh b/build_sysroot/build_sysroot.sh
index 37aa7c1908d..26f6607b2aa 100755
--- a/build_sysroot/build_sysroot.sh
+++ b/build_sysroot/build_sysroot.sh
@@ -29,14 +29,3 @@ fi
 # Copy files to sysroot
 mkdir -p sysroot/lib/rustlib/$TARGET_TRIPLE/lib/
 cp -r target/$TARGET_TRIPLE/$sysroot_channel/deps/* sysroot/lib/rustlib/$TARGET_TRIPLE/lib/
-
-if [[ "$1" == "--release" ]]; then
-    channel='release'
-    RUSTFLAGS="$RUSTFLAGS -Zmir-opt-level=3" cargo build --target $TARGET_TRIPLE --release --manifest-path ./sysroot_src/src/libtest/Cargo.toml
-else
-    channel='debug'
-    cargo build --target $TARGET_TRIPLE --manifest-path ./sysroot_src/src/libtest/Cargo.toml
-fi
-
-# Copy files to sysroot
-cp -r sysroot_src/src/libtest/target/$TARGET_TRIPLE/$sysroot_channel/deps/*  sysroot/lib/rustlib/$TARGET_TRIPLE/lib/
diff --git a/build_sysroot/rustc-std-workspace-alloc/Cargo.toml b/build_sysroot/rustc-std-workspace-alloc/Cargo.toml
deleted file mode 100644
index 221365373ff..00000000000
--- a/build_sysroot/rustc-std-workspace-alloc/Cargo.toml
+++ /dev/null
@@ -1,15 +0,0 @@
-[package]
-name = "rustc-std-workspace-alloc"
-version = "1.0.0"
-authors = ["Alex Crichton <alex@alexcrichton.com>"]
-license = 'MIT/Apache-2.0'
-description = """
-Hack for the compiler's own build system
-"""
-edition = "2018"
-
-[lib]
-path = "lib.rs"
-
-[dependencies]
-alloc = { path = "../sysroot_src/src/liballoc" }
diff --git a/build_sysroot/rustc-std-workspace-alloc/lib.rs b/build_sysroot/rustc-std-workspace-alloc/lib.rs
deleted file mode 100644
index cf216ec9d29..00000000000
--- a/build_sysroot/rustc-std-workspace-alloc/lib.rs
+++ /dev/null
@@ -1,5 +0,0 @@
-#![feature(no_core)]
-#![no_core]
-#![deny(rust_2018_idioms)]
-
-pub use ::alloc::*;
diff --git a/patches/0020-libtest-Don-t-require-panic_unwind.patch b/patches/0020-libtest-Don-t-require-panic_unwind.patch
new file mode 100644
index 00000000000..4b46914c34b
--- /dev/null
+++ b/patches/0020-libtest-Don-t-require-panic_unwind.patch
@@ -0,0 +1,41 @@
+From 7b30ddc41c71e89d3e6ab6840b0206877d68f201 Mon Sep 17 00:00:00 2001
+From: bjorn3 <bjorn3@users.noreply.github.com>
+Date: Sun, 25 Aug 2019 16:23:06 +0200
+Subject: [PATCH] [libtest] Don't require panic_unwind
+
+---
+ src/libtest/lib.rs | 11 -----------
+ 1 file changed, 11 deletions(-)
+
+diff --git a/src/libtest/lib.rs b/src/libtest/lib.rs
+index 9bb76f9..c5fe1aa 100644
+--- a/src/libtest/lib.rs
++++ b/src/libtest/lib.rs
+@@ -24,7 +24,6 @@
+ #![cfg_attr(any(unix, target_os = "cloudabi"), feature(libc, rustc_private))]
+ #![feature(nll)]
+ #![feature(set_stdio)]
+-#![feature(panic_unwind)]
+ #![feature(staged_api)]
+ #![feature(termination_trait_lib)]
+ #![feature(test)]
+@@ -34,16 +33,6 @@ use getopts;
+ extern crate libc;
+ use term;
+ 
+-// FIXME(#54291): rustc and/or LLVM don't yet support building with panic-unwind
+-//                on aarch64-pc-windows-msvc, or thumbv7a-pc-windows-msvc
+-//                so we don't link libtest against libunwind (for the time being)
+-//                even though it means that libtest won't be fully functional on
+-//                these platforms.
+-//
+-// See also: https://github.com/rust-lang/rust/issues/54190#issuecomment-422904437
+-#[cfg(not(all(windows, any(target_arch = "aarch64", target_arch = "arm"))))]
+-extern crate panic_unwind;
+-
+ pub use self::ColorConfig::*;
+ use self::NamePadding::*;
+ use self::OutputLocation::*;
+-- 
+2.20.1
+