diff --git a/build_library/catalyst_toolchains.sh b/build_library/catalyst_toolchains.sh
index 07428f7350..2ab4c46dae 100644
--- a/build_library/catalyst_toolchains.sh
+++ b/build_library/catalyst_toolchains.sh
@@ -19,17 +19,22 @@ configure_target_root() {
     CBUILD="$(portageq envvar CBUILD)" \
         CHOST="${cross_chost}" \
         ROOT="/build/${board}" \
-        SYSROOT="/usr/${cross_chost}" \
+        SYSROOT="/build/${board}" \
         _configure_sysroot "${profile}"
 }
 
 build_target_toolchain() {
     local board="$1"
     local ROOT="/build/${board}"
+    local SYSROOT="/usr/$(get_board_chost "${board}")"
+
+    mkdir -p "${ROOT}/usr"
+    cp -at "${ROOT}" "${SYSROOT}"/lib*
+    cp -at "${ROOT}"/usr "${SYSROOT}"/usr/include "${SYSROOT}"/usr/lib*
 
     # --root is required because run_merge overrides ROOT=
     PORTAGE_CONFIGROOT="$ROOT" \
-        run_merge -u --root="$ROOT" "${TOOLCHAIN_PKGS[@]}"
+        run_merge -u --root="$ROOT" --sysroot="$ROOT" "${TOOLCHAIN_PKGS[@]}"
 }
 
 configure_crossdev_overlay / /tmp/crossdev
diff --git a/build_library/toolchain_util.sh b/build_library/toolchain_util.sh
index d8649a12d1..53f829a4b4 100644
--- a/build_library/toolchain_util.sh
+++ b/build_library/toolchain_util.sh
@@ -257,7 +257,7 @@ _configure_sysroot() {
     $sudo eselect profile set --force "$profile"
 
     $sudo tee "${ROOT}/etc/portage/make.conf" >/dev/null <<EOF
-$(portageq envvar -v CHOST CBUILD ROOT SYSROOT \
+$(portageq envvar -v CHOST CBUILD ROOT \
     PORTDIR PORTDIR_OVERLAY DISTDIR PKGDIR)
 HOSTCC=\${CBUILD}-gcc
 PKG_CONFIG_PATH="\${SYSROOT}/usr/lib/pkgconfig/"
@@ -372,7 +372,7 @@ install_cross_libs() {
     done | $sudo tee "${package_provided}/cross-${cross_chost}" >/dev/null
 
     # OK, clear as mud? Install those dependencies now!
-    PORTAGE_CONFIGROOT="$ROOT" ROOT="$ROOT" $sudo emerge "$@" -u $cross_deps
+    PORTAGE_CONFIGROOT="$ROOT" $sudo emerge --root="$ROOT" --sysroot="$ROOT" "$@" -u $cross_deps
 }
 
 # Get the latest GCC profile for a given CHOST