diff --git a/src/bootstrap/src/core/config/config.rs b/src/bootstrap/src/core/config/config.rs
index e32288e2caf6..3435225af7bd 100644
--- a/src/bootstrap/src/core/config/config.rs
+++ b/src/bootstrap/src/core/config/config.rs
@@ -2404,8 +2404,11 @@ impl Config {
             .unwrap_or_else(|| SplitDebuginfo::default_for_platform(target))
     }
 
-    pub fn submodules(&self, rust_info: &GitInfo) -> bool {
-        self.submodules.unwrap_or(rust_info.is_managed_git_subrepository())
+    /// Returns whether or not submodules should be managed by bootstrap.
+    pub fn submodules(&self) -> bool {
+        // If not specified in config, the default is to only manage
+        // submodules if we're currently inside a git repository.
+        self.submodules.unwrap_or(self.rust_info.is_managed_git_subrepository())
     }
 
     pub fn codegen_backends(&self, target: TargetSelection) -> &[String] {
diff --git a/src/bootstrap/src/lib.rs b/src/bootstrap/src/lib.rs
index ab640bf39aae..e8f412d785d5 100644
--- a/src/bootstrap/src/lib.rs
+++ b/src/bootstrap/src/lib.rs
@@ -475,7 +475,7 @@ impl Build {
     ///
     /// `relative_path` should be relative to the root of the git repository, not an absolute path.
     pub(crate) fn update_submodule(&self, relative_path: &Path) {
-        if !self.config.submodules(self.rust_info()) {
+        if !self.config.submodules() {
             return;
         }
 
@@ -585,7 +585,7 @@ impl Build {
     fn update_existing_submodules(&self) {
         // Avoid running git when there isn't a git checkout, or the user has
         // explicitly disabled submodules in `config.toml`.
-        if !self.config.submodules(self.rust_info()) {
+        if !self.config.submodules() {
             return;
         }
         let output = helpers::git(Some(&self.src))
@@ -609,7 +609,7 @@ impl Build {
     /// Updates the given submodule only if it's initialized already; nothing happens otherwise.
     pub fn update_existing_submodule(&self, submodule: &Path) {
         // Avoid running git when there isn't a git checkout.
-        if !self.config.submodules(self.rust_info()) {
+        if !self.config.submodules() {
             return;
         }