diff --git a/build_system/build_backend.rs b/build_system/build_backend.rs
index 00de86007a86..dfbf900b2eef 100644
--- a/build_system/build_backend.rs
+++ b/build_system/build_backend.rs
@@ -6,7 +6,7 @@ use crate::rustc_info::get_file_name;
 use crate::shared_utils::{rustflags_from_env, rustflags_to_cmd_env};
 use crate::utils::{CargoProject, Compiler, LogGroup};
 
-pub(crate) static CG_CLIF: CargoProject = CargoProject::new(&RelPath::SOURCE, "cg_clif");
+static CG_CLIF: CargoProject = CargoProject::new(&RelPath::SOURCE, "cg_clif");
 
 pub(crate) fn build_backend(
     dirs: &Dirs,
diff --git a/build_system/build_sysroot.rs b/build_system/build_sysroot.rs
index 01fbef179e3d..b8a995f183da 100644
--- a/build_system/build_sysroot.rs
+++ b/build_system/build_sysroot.rs
@@ -3,7 +3,8 @@ use std::process::Command;
 use std::{env, fs};
 
 use crate::path::{Dirs, RelPath};
-use crate::rustc_info::get_file_name;
+use crate::prepare::apply_patches;
+use crate::rustc_info::{get_default_sysroot, get_file_name};
 use crate::utils::{
     remove_dir_if_exists, spawn_and_wait, try_hard_link, CargoProject, Compiler, LogGroup,
 };
@@ -157,10 +158,10 @@ impl SysrootTarget {
     }
 }
 
-pub(crate) static STDLIB_SRC: RelPath = RelPath::BUILD.join("stdlib");
-pub(crate) static STANDARD_LIBRARY: CargoProject =
+static STDLIB_SRC: RelPath = RelPath::BUILD.join("stdlib");
+static STANDARD_LIBRARY: CargoProject =
     CargoProject::new(&STDLIB_SRC.join("library/sysroot"), "stdlib_target");
-pub(crate) static RTSTARTUP_SYSROOT: RelPath = RelPath::BUILD.join("rtstartup");
+static RTSTARTUP_SYSROOT: RelPath = RelPath::BUILD.join("rtstartup");
 
 fn build_sysroot_for_triple(
     dirs: &Dirs,
@@ -285,7 +286,10 @@ fn build_clif_sysroot_for_triple(
 
 fn build_rtstartup(dirs: &Dirs, compiler: &Compiler) -> Option<SysrootTarget> {
     if !config::get_bool("keep_sysroot") {
-        crate::prepare::prepare_stdlib(dirs, &compiler.rustc);
+        let sysroot_src_orig = get_default_sysroot(&compiler.rustc).join("lib/rustlib/src/rust");
+        assert!(sysroot_src_orig.exists());
+
+        apply_patches(dirs, "stdlib", &sysroot_src_orig, &STDLIB_SRC.to_path(dirs));
     }
 
     if !compiler.triple.ends_with("windows-gnu") {
diff --git a/build_system/prepare.rs b/build_system/prepare.rs
index ad6062674021..387feb41251b 100644
--- a/build_system/prepare.rs
+++ b/build_system/prepare.rs
@@ -4,9 +4,7 @@ use std::hash::{Hash, Hasher};
 use std::path::{Path, PathBuf};
 use std::process::Command;
 
-use crate::build_sysroot::STDLIB_SRC;
 use crate::path::{Dirs, RelPath};
-use crate::rustc_info::get_default_sysroot;
 use crate::utils::{
     copy_dir_recursively, remove_dir_if_exists, retry_spawn_and_wait, spawn_and_wait,
 };
@@ -17,13 +15,6 @@ pub(crate) fn prepare(dirs: &Dirs) {
     crate::tests::REGEX_REPO.fetch(dirs);
 }
 
-pub(crate) fn prepare_stdlib(dirs: &Dirs, rustc: &Path) {
-    let sysroot_src_orig = get_default_sysroot(rustc).join("lib/rustlib/src/rust");
-    assert!(sysroot_src_orig.exists());
-
-    apply_patches(dirs, "stdlib", &sysroot_src_orig, &STDLIB_SRC.to_path(dirs));
-}
-
 pub(crate) struct GitRepo {
     url: GitRepoUrl,
     rev: &'static str,
diff --git a/build_system/tests.rs b/build_system/tests.rs
index 22a791bfc7d2..0d158c21c036 100644
--- a/build_system/tests.rs
+++ b/build_system/tests.rs
@@ -117,7 +117,7 @@ pub(crate) static RAND_REPO: GitRepo = GitRepo::github(
     "rand",
 );
 
-pub(crate) static RAND: CargoProject = CargoProject::new(&RAND_REPO.source_dir(), "rand_target");
+static RAND: CargoProject = CargoProject::new(&RAND_REPO.source_dir(), "rand_target");
 
 pub(crate) static REGEX_REPO: GitRepo = GitRepo::github(
     "rust-lang",
@@ -127,12 +127,11 @@ pub(crate) static REGEX_REPO: GitRepo = GitRepo::github(
     "regex",
 );
 
-pub(crate) static REGEX: CargoProject = CargoProject::new(&REGEX_REPO.source_dir(), "regex_target");
+static REGEX: CargoProject = CargoProject::new(&REGEX_REPO.source_dir(), "regex_target");
 
-pub(crate) static PORTABLE_SIMD_SRC: RelPath = RelPath::BUILD.join("portable-simd");
+static PORTABLE_SIMD_SRC: RelPath = RelPath::BUILD.join("portable-simd");
 
-pub(crate) static PORTABLE_SIMD: CargoProject =
-    CargoProject::new(&PORTABLE_SIMD_SRC, "portable-simd_target");
+static PORTABLE_SIMD: CargoProject = CargoProject::new(&PORTABLE_SIMD_SRC, "portable-simd_target");
 
 static LIBCORE_TESTS_SRC: RelPath = RelPath::BUILD.join("coretests");