diff --git a/book/src/allowlisting.md b/book/src/allowlisting.md
index 2e28d80ff6..edf93df0ef 100644
--- a/book/src/allowlisting.md
+++ b/book/src/allowlisting.md
@@ -19,12 +19,14 @@ transitively used by a definition that matches them.
 * [`bindgen::Builder::allowlist_type`](https://docs.rs/bindgen/latest/bindgen/struct.Builder.html#method.allowlist_type)
 * [`bindgen::Builder::allowlist_function`](https://docs.rs/bindgen/latest/bindgen/struct.Builder.html#method.allowlist_function)
 * [`bindgen::Builder::allowlist_var`](https://docs.rs/bindgen/latest/bindgen/struct.Builder.html#method.allowlist_var)
+* [`bindgen::Builder::allowlist_file`](https://docs.rs/bindgen/latest/bindgen/struct.Builder.html#method.allowlist_file)
 
 ### Command Line
 
 * `--allowlist-type <type>`
 * `--allowlist-function <function>`
 * `--allowlist-var <var>`
+* `--allowlist-file <path>`
 
 ### Annotations
 
diff --git a/src/ir/context.rs b/src/ir/context.rs
index b2e6f98542..9afd16d6a6 100644
--- a/src/ir/context.rs
+++ b/src/ir/context.rs
@@ -2296,7 +2296,8 @@ If you encounter an error missing from this list, please file an issue or a PR!"
                     // game.
                     if self.options().allowlisted_types.is_empty() &&
                         self.options().allowlisted_functions.is_empty() &&
-                        self.options().allowlisted_vars.is_empty()
+                        self.options().allowlisted_vars.is_empty() &&
+                        self.options().allowlisted_files.is_empty()
                     {
                         return true;
                     }
@@ -2307,6 +2308,23 @@ If you encounter an error missing from this list, please file an issue or a PR!"
                         return true;
                     }
 
+                    // Items with a source location in an explicitly allowlisted file
+                    // are always included.
+                    if !self.options().allowlisted_files.is_empty() {
+                        if let Some(location) = item.location() {
+                            let (file, _, _, _) = location.location();
+                            if let Some(filename) = file.name() {
+                                if self
+                                    .options()
+                                    .allowlisted_files
+                                    .matches(&filename)
+                                {
+                                    return true;
+                                }
+                            }
+                        }
+                    }
+
                     let name = item.path_for_allowlisting(self)[1..].join("::");
                     debug!("allowlisted_items: testing {:?}", name);
                     match *item.kind() {
diff --git a/src/ir/item.rs b/src/ir/item.rs
index 8692575fe9..aed575ca11 100644
--- a/src/ir/item.rs
+++ b/src/ir/item.rs
@@ -530,6 +530,11 @@ impl Item {
         &mut self.kind
     }
 
+    /// Where in the source is this item located?
+    pub fn location(&self) -> Option<&clang::SourceLocation> {
+        self.location.as_ref()
+    }
+
     /// Get an identifier that differentiates this item from its siblings.
     ///
     /// This should stay relatively stable in the face of code motion outside or
diff --git a/src/lib.rs b/src/lib.rs
index 39f55f04ff..ea5c61b405 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -313,6 +313,7 @@ impl Builder {
             (&self.options.allowlisted_functions, "--allowlist-function"),
             (&self.options.allowlisted_types, "--allowlist-type"),
             (&self.options.allowlisted_vars, "--allowlist-var"),
+            (&self.options.allowlisted_files, "--allowlist-file"),
             (&self.options.no_partialeq_types, "--no-partialeq"),
             (&self.options.no_copy_types, "--no-copy"),
             (&self.options.no_debug_types, "--no-debug"),
@@ -908,6 +909,12 @@ impl Builder {
         self
     }
 
+    /// Allowlist the given file so that its contents appear in the generated bindings.
+    pub fn allowlist_file<T: AsRef<str>>(mut self, arg: T) -> Builder {
+        self.options.allowlisted_files.insert(arg);
+        self
+    }
+
     /// Deprecated: use allowlist_var instead.
     #[deprecated(note = "use allowlist_var instead")]
     pub fn whitelist_var<T: AsRef<str>>(self, arg: T) -> Builder {
@@ -1705,6 +1712,9 @@ struct BindgenOptions {
     /// Allowlisted variables. See docs for `allowlisted_types` for more.
     allowlisted_vars: RegexSet,
 
+    /// The set of files whose contents should be allowlisted.
+    allowlisted_files: RegexSet,
+
     /// The default style of code to generate for enums
     default_enum_style: codegen::EnumVariation,
 
@@ -1984,6 +1994,7 @@ impl BindgenOptions {
             &mut self.allowlisted_vars,
             &mut self.allowlisted_types,
             &mut self.allowlisted_functions,
+            &mut self.allowlisted_files,
             &mut self.blocklisted_types,
             &mut self.blocklisted_functions,
             &mut self.blocklisted_items,
@@ -2042,6 +2053,7 @@ impl Default for BindgenOptions {
             allowlisted_types: Default::default(),
             allowlisted_functions: Default::default(),
             allowlisted_vars: Default::default(),
+            allowlisted_files: Default::default(),
             default_enum_style: Default::default(),
             bitfield_enums: Default::default(),
             newtype_enums: Default::default(),
diff --git a/src/options.rs b/src/options.rs
index 67bcda74fc..04d42ed5c3 100644
--- a/src/options.rs
+++ b/src/options.rs
@@ -418,6 +418,14 @@ where
                 .takes_value(true)
                 .multiple_occurrences(true)
                 .number_of_values(1),
+            Arg::new("allowlist-file")
+                .alias("allowlist-file")
+                .long("allowlist-file")
+                .help("Allowlist all contents of <path>.")
+                .value_name("path")
+                .takes_value(true)
+                .multiple_occurrences(true)
+                .number_of_values(1),
             Arg::new("verbose")
                 .long("verbose")
                 .help("Print verbose error messages."),
@@ -871,6 +879,12 @@ where
         }
     }
 
+    if let Some(hidden_files) = matches.values_of("allowlist-file") {
+        for file in hidden_files {
+            builder = builder.allowlist_file(file);
+        }
+    }
+
     if let Some(args) = matches.values_of("clang-args") {
         for arg in args {
             builder = builder.clang_arg(arg);
diff --git a/tests/expectations/tests/allowlist-file.rs b/tests/expectations/tests/allowlist-file.rs
new file mode 100644
index 0000000000..2c2660a606
--- /dev/null
+++ b/tests/expectations/tests/allowlist-file.rs
@@ -0,0 +1,154 @@
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
+
+pub const SOME_DEFUN: u32 = 123;
+extern "C" {
+    #[link_name = "\u{1}_Z12SomeFunctionv"]
+    pub fn SomeFunction();
+}
+extern "C" {
+    pub static mut someVar: ::std::os::raw::c_int;
+}
+#[repr(C)]
+#[derive(Debug, Default, Copy, Clone)]
+pub struct someClass {
+    pub _address: u8,
+}
+#[test]
+fn bindgen_test_layout_someClass() {
+    assert_eq!(
+        ::std::mem::size_of::<someClass>(),
+        1usize,
+        concat!("Size of: ", stringify!(someClass))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<someClass>(),
+        1usize,
+        concat!("Alignment of ", stringify!(someClass))
+    );
+}
+extern "C" {
+    #[link_name = "\u{1}_ZN9someClass16somePublicMethodEi"]
+    pub fn someClass_somePublicMethod(
+        this: *mut someClass,
+        foo: ::std::os::raw::c_int,
+    );
+}
+impl someClass {
+    #[inline]
+    pub unsafe fn somePublicMethod(&mut self, foo: ::std::os::raw::c_int) {
+        someClass_somePublicMethod(self, foo)
+    }
+}
+extern "C" {
+    pub fn ExternFunction();
+}
+extern "C" {
+    #[link_name = "\u{1}_ZN3foo18NamespacedFunctionEv"]
+    pub fn foo_NamespacedFunction();
+}
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct StructWithAllowlistedDefinition {
+    pub other: *mut StructWithAllowlistedFwdDecl,
+}
+#[test]
+fn bindgen_test_layout_StructWithAllowlistedDefinition() {
+    assert_eq!(
+        ::std::mem::size_of::<StructWithAllowlistedDefinition>(),
+        8usize,
+        concat!("Size of: ", stringify!(StructWithAllowlistedDefinition))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<StructWithAllowlistedDefinition>(),
+        8usize,
+        concat!("Alignment of ", stringify!(StructWithAllowlistedDefinition))
+    );
+    assert_eq!(
+        unsafe {
+            &(*(::std::ptr::null::<StructWithAllowlistedDefinition>())).other
+                as *const _ as usize
+        },
+        0usize,
+        concat!(
+            "Offset of field: ",
+            stringify!(StructWithAllowlistedDefinition),
+            "::",
+            stringify!(other)
+        )
+    );
+}
+impl Default for StructWithAllowlistedDefinition {
+    fn default() -> Self {
+        let mut s = ::std::mem::MaybeUninit::<Self>::uninit();
+        unsafe {
+            ::std::ptr::write_bytes(s.as_mut_ptr(), 0, 1);
+            s.assume_init()
+        }
+    }
+}
+#[repr(C)]
+#[derive(Debug, Default, Copy, Clone)]
+pub struct StructWithAllowlistedFwdDecl {
+    pub b: ::std::os::raw::c_int,
+}
+#[test]
+fn bindgen_test_layout_StructWithAllowlistedFwdDecl() {
+    assert_eq!(
+        ::std::mem::size_of::<StructWithAllowlistedFwdDecl>(),
+        4usize,
+        concat!("Size of: ", stringify!(StructWithAllowlistedFwdDecl))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<StructWithAllowlistedFwdDecl>(),
+        4usize,
+        concat!("Alignment of ", stringify!(StructWithAllowlistedFwdDecl))
+    );
+    assert_eq!(
+        unsafe {
+            &(*(::std::ptr::null::<StructWithAllowlistedFwdDecl>())).b
+                as *const _ as usize
+        },
+        0usize,
+        concat!(
+            "Offset of field: ",
+            stringify!(StructWithAllowlistedFwdDecl),
+            "::",
+            stringify!(b)
+        )
+    );
+}
+#[repr(C)]
+#[derive(Debug, Default, Copy, Clone)]
+pub struct AllowlistMe {
+    pub foo: ::std::os::raw::c_int,
+}
+#[test]
+fn bindgen_test_layout_AllowlistMe() {
+    assert_eq!(
+        ::std::mem::size_of::<AllowlistMe>(),
+        4usize,
+        concat!("Size of: ", stringify!(AllowlistMe))
+    );
+    assert_eq!(
+        ::std::mem::align_of::<AllowlistMe>(),
+        4usize,
+        concat!("Alignment of ", stringify!(AllowlistMe))
+    );
+    assert_eq!(
+        unsafe {
+            &(*(::std::ptr::null::<AllowlistMe>())).foo as *const _ as usize
+        },
+        0usize,
+        concat!(
+            "Offset of field: ",
+            stringify!(AllowlistMe),
+            "::",
+            stringify!(foo)
+        )
+    );
+}
diff --git a/tests/headers/allowlist-file.hpp b/tests/headers/allowlist-file.hpp
new file mode 100644
index 0000000000..b0354a047f
--- /dev/null
+++ b/tests/headers/allowlist-file.hpp
@@ -0,0 +1,21 @@
+// bindgen-flags: --allowlist-file ".*/allowlisted/file.*" --allowlist-type AllowlistMe -- -Itests/headers
+
+
+// Forward declaration of struct that's defined in an allowlisted file.
+struct StructWithAllowlistedDefinition;
+
+#include "allowlisted/file.hpp"
+
+// Actual definition of struct that has a forward declaration in an allowlisted file.
+struct StructWithAllowlistedFwdDecl {
+    int b;
+};
+
+class Ignored {
+    char c;
+};
+
+// Also have an explicitly allowlisted type
+class AllowlistMe {
+    int foo;
+};
diff --git a/tests/headers/allowlisted/file.hpp b/tests/headers/allowlisted/file.hpp
new file mode 100644
index 0000000000..5f360e5ea9
--- /dev/null
+++ b/tests/headers/allowlisted/file.hpp
@@ -0,0 +1,22 @@
+void SomeFunction();
+extern int someVar;
+#define SOME_DEFUN 123
+
+class someClass {
+  void somePrivateMethod();
+public:
+  void somePublicMethod(int foo);
+};
+
+extern "C" void ExternFunction();
+
+namespace foo {
+  void NamespacedFunction();
+}
+
+
+struct StructWithAllowlistedFwdDecl;
+
+struct StructWithAllowlistedDefinition {
+    StructWithAllowlistedFwdDecl* other;
+};