diff --git a/compiler/rustc_driver_impl/src/lib.rs b/compiler/rustc_driver_impl/src/lib.rs
index d2c4335cf2b..78ba841d89f 100644
--- a/compiler/rustc_driver_impl/src/lib.rs
+++ b/compiler/rustc_driver_impl/src/lib.rs
@@ -937,7 +937,7 @@ fn usage(verbose: bool, include_unstable_options: bool, nightly_build: bool) {
     let groups = if verbose { config::rustc_optgroups() } else { config::rustc_short_optgroups() };
     let mut options = getopts::Options::new();
     for option in groups.iter().filter(|x| include_unstable_options || x.is_stable()) {
-        (option.apply)(&mut options);
+        option.apply(&mut options);
     }
     let message = "Usage: rustc [OPTIONS] INPUT";
     let nightly_help = if nightly_build {
@@ -1219,7 +1219,7 @@ pub fn handle_options(early_dcx: &EarlyDiagCtxt, args: &[String]) -> Option<geto
     let mut options = getopts::Options::new();
     let optgroups = config::rustc_optgroups();
     for option in &optgroups {
-        (option.apply)(&mut options);
+        option.apply(&mut options);
     }
     let matches = options.parse(args).unwrap_or_else(|e| {
         let msg: Option<String> = match e {
@@ -1233,7 +1233,7 @@ pub fn handle_options(early_dcx: &EarlyDiagCtxt, args: &[String]) -> Option<geto
                 optgroups.iter().find(|option| option.name == opt).map(|option| {
                     // Print the help just for the option in question.
                     let mut options = getopts::Options::new();
-                    (option.apply)(&mut options);
+                    option.apply(&mut options);
                     // getopt requires us to pass a function for joining an iterator of
                     // strings, even though in this case we expect exactly one string.
                     options.usage_with_format(|it| {
diff --git a/compiler/rustc_interface/src/tests.rs b/compiler/rustc_interface/src/tests.rs
index ce90ceeda56..2361231b3fb 100644
--- a/compiler/rustc_interface/src/tests.rs
+++ b/compiler/rustc_interface/src/tests.rs
@@ -102,7 +102,7 @@ fn new_public_extern_entry<S, I>(locations: I) -> ExternEntry
 fn optgroups() -> getopts::Options {
     let mut opts = getopts::Options::new();
     for group in rustc_optgroups() {
-        (group.apply)(&mut opts);
+        group.apply(&mut opts);
     }
     return opts;
 }
diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs
index fe05605c1b9..0c4827ef54d 100644
--- a/compiler/rustc_session/src/config.rs
+++ b/compiler/rustc_session/src/config.rs
@@ -1373,7 +1373,7 @@ enum OptionStability {
 }
 
 pub struct RustcOptGroup {
-    pub apply: Box<dyn Fn(&mut getopts::Options) -> &mut getopts::Options>,
+    apply: Box<dyn Fn(&mut getopts::Options) -> &mut getopts::Options>,
     pub name: &'static str,
     stability: OptionStability,
 }
@@ -1383,6 +1383,10 @@ pub fn is_stable(&self) -> bool {
         self.stability == OptionStability::Stable
     }
 
+    pub fn apply(&self, options: &mut getopts::Options) {
+        (self.apply)(options);
+    }
+
     pub fn stable<F>(name: &'static str, f: F) -> RustcOptGroup
     where
         F: Fn(&mut getopts::Options) -> &mut getopts::Options + 'static,
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index 7c9dcd41e6a..40e649915cf 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -685,7 +685,7 @@ fn opts() -> Vec<RustcOptGroup> {
 fn usage(argv0: &str) {
     let mut options = getopts::Options::new();
     for option in opts() {
-        (option.apply)(&mut options);
+        option.apply(&mut options);
     }
     println!("{}", options.usage(&format!("{argv0} [options] <input>")));
     println!("    @path               Read newline separated options from `path`\n");
@@ -769,7 +769,7 @@ fn main_args(
 
     let mut options = getopts::Options::new();
     for option in opts() {
-        (option.apply)(&mut options);
+        option.apply(&mut options);
     }
     let matches = match options.parse(&args) {
         Ok(m) => m,