From c48a0f3e6d70c3e9beb0473c8181dfd57adc9c59 Mon Sep 17 00:00:00 2001
From: chertov <chertovmv@gmail.com>
Date: Mon, 13 Oct 2025 12:58:50 +0700
Subject: [PATCH 1/3] Allow generating hidden visibility functions

---
 bindgen/ir/function.rs |  6 +++++-
 bindgen/options/mod.rs | 12 ++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/bindgen/ir/function.rs b/bindgen/ir/function.rs
index 6f8c00fa89..d17f803d6f 100644
--- a/bindgen/ir/function.rs
+++ b/bindgen/ir/function.rs
@@ -730,7 +730,11 @@ impl ClangSubItemParser for Function {
 
         debug!("Function::parse({cursor:?}, {:?})", cursor.cur_type());
         let visibility = cursor.visibility();
-        if visibility != CXVisibility_Default {
+        let allow_hidden = context.options().generate_hidden_functions &&
+            (visibility == CXVisibility_Hidden ||
+                visibility == CXVisibility_Protected);
+
+        if visibility != CXVisibility_Default && !allow_hidden {
             return Err(ParseError::Continue);
         }
         if cursor.access_specifier() == CX_CXXPrivate &&
diff --git a/bindgen/options/mod.rs b/bindgen/options/mod.rs
index b9b33a850b..a1915d85c2 100644
--- a/bindgen/options/mod.rs
+++ b/bindgen/options/mod.rs
@@ -2329,4 +2329,16 @@ options! {
         },
         as_args: "--generate-private-functions",
     },
+    /// Whether to allow generating functions that are marked with hidden or protected visibility.
+    generate_hidden_functions: bool {
+        methods: {
+            /// Set whether to generate functions that are not externally visible according to clang.
+            pub fn generate_hidden_functions(mut self, doit: bool) -> Self {
+                self.options.generate_hidden_functions = doit;
+                self
+            }
+
+        },
+        as_args: "--generate-hidden-functions",
+    },
 }

From 0d28b509debf51a69de7b0e99021fc3ef1aef4f7 Mon Sep 17 00:00:00 2001
From: chertov <chertovmv@gmail.com>
Date: Tue, 14 Oct 2025 23:33:59 +0700
Subject: [PATCH 2/3] Add regression tests for generate_hidden_functions option

---
 bindgen-tests/tests/tests.rs | 48 ++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/bindgen-tests/tests/tests.rs b/bindgen-tests/tests/tests.rs
index 6e3c358d3e..bfd56f1cc3 100644
--- a/bindgen-tests/tests/tests.rs
+++ b/bindgen-tests/tests/tests.rs
@@ -427,6 +427,54 @@ fn test_header_contents() {
     assert_eq!(expected, actual);
 }
 
+const HIDDEN_FUNCTIONS_HEADER: &str = r#"
+__attribute__((visibility("hidden"))) int hidden_fn(void);
+__attribute__((visibility("protected"))) int protected_fn(void);
+int visible_fn(void);
+"#;
+
+fn hidden_functions_builder() -> Builder {
+    builder()
+        .allowlist_function("visible_fn")
+        .allowlist_function("hidden_fn")
+        .allowlist_function("protected_fn")
+        .header_contents("hidden.h", HIDDEN_FUNCTIONS_HEADER)
+}
+
+#[test]
+fn hidden_functions_are_skipped_by_default() {
+    let bindings = hidden_functions_builder()
+        .generate()
+        .unwrap()
+        .to_string();
+
+    assert!(bindings.contains("pub fn visible_fn"));
+    assert!(!bindings.contains("pub fn hidden_fn"));
+}
+
+#[test]
+fn hidden_functions_can_be_generated_when_enabled() {
+    let default_bindings = hidden_functions_builder()
+        .generate()
+        .unwrap()
+        .to_string();
+
+    let hidden_enabled = hidden_functions_builder()
+        .generate_hidden_functions(true)
+        .generate()
+        .unwrap()
+        .to_string();
+
+    assert!(hidden_enabled.contains("pub fn hidden_fn"));
+    assert!(!default_bindings.contains("pub fn hidden_fn"));
+
+    // Clang on Mach-O downgrades `protected` visibility to `default`,
+    // so the symbol might already be present without the new option.
+    if !default_bindings.contains("pub fn protected_fn") {
+        assert!(hidden_enabled.contains("pub fn protected_fn"));
+    }
+}
+
 #[test]
 fn test_multiple_header_calls_in_builder() {
     let actual = builder()

From 5c6e371e6c2194c147d2d1855acc5b71bce792e4 Mon Sep 17 00:00:00 2001
From: chertov <chertovmv@gmail.com>
Date: Tue, 14 Oct 2025 23:33:59 +0700
Subject: [PATCH 3/3] Add regression tests for generate_hidden_functions option

# Conflicts:
#	bindgen-tests/tests/tests.rs
---
 bindgen-tests/tests/tests.rs | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/bindgen-tests/tests/tests.rs b/bindgen-tests/tests/tests.rs
index bfd56f1cc3..cd21f5f9ba 100644
--- a/bindgen-tests/tests/tests.rs
+++ b/bindgen-tests/tests/tests.rs
@@ -443,10 +443,7 @@ fn hidden_functions_builder() -> Builder {
 
 #[test]
 fn hidden_functions_are_skipped_by_default() {
-    let bindings = hidden_functions_builder()
-        .generate()
-        .unwrap()
-        .to_string();
+    let bindings = hidden_functions_builder().generate().unwrap().to_string();
 
     assert!(bindings.contains("pub fn visible_fn"));
     assert!(!bindings.contains("pub fn hidden_fn"));
@@ -454,10 +451,8 @@ fn hidden_functions_are_skipped_by_default() {
 
 #[test]
 fn hidden_functions_can_be_generated_when_enabled() {
-    let default_bindings = hidden_functions_builder()
-        .generate()
-        .unwrap()
-        .to_string();
+    let default_bindings =
+        hidden_functions_builder().generate().unwrap().to_string();
 
     let hidden_enabled = hidden_functions_builder()
         .generate_hidden_functions(true)