4 files changed, 18 insertions, 5 deletions
diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index 43d6b9b9e90..0fee3ff3218 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -10,7 +10,7 @@
 
 // The Rust abstract syntax tree.
 
-use codemap::{Span, Spanned, DUMMY_SP};
+use codemap::{Span, Spanned, DUMMY_SP, ExpnId};
 use abi::Abi;
 use ast_util;
 use owned_slice::OwnedSlice;
@@ -984,7 +984,7 @@ pub struct InlineAsm {
     pub volatile: bool,
     pub alignstack: bool,
     pub dialect: AsmDialect,
-    pub expn_id: u32,
+    pub expn_id: ExpnId,
 }
 
 /// represents an argument in a function header
diff --git a/src/libsyntax/codemap.rs b/src/libsyntax/codemap.rs
index d44de7862a3..e9b2556c53e 100644
--- a/src/libsyntax/codemap.rs
+++ b/src/libsyntax/codemap.rs
@@ -26,6 +26,7 @@ source code snippets, etc.
 use serialize::{Encodable, Decodable, Encoder, Decoder};
 use std::cell::RefCell;
 use std::rc::Rc;
+use libc::c_uint;
 
 pub trait Pos {
     fn from_uint(n: uint) -> Self;
@@ -223,11 +224,22 @@ pub struct ExpnInfo {
     pub callee: NameAndSpan
 }
 
-#[deriving(PartialEq, Eq, Clone, Show, Hash)]
-pub struct ExpnId(pub u32);
+#[deriving(PartialEq, Eq, Clone, Show, Hash, Encodable, Decodable)]
+pub struct ExpnId(u32);
 
 pub static NO_EXPANSION: ExpnId = ExpnId(-1);
 
+impl ExpnId {
+    pub fn from_llvm_cookie(cookie: c_uint) -> ExpnId {
+        ExpnId(cookie as u32)
+    }
+
+    pub fn to_llvm_cookie(self) -> i32 {
+        let ExpnId(cookie) = self;
+        cookie as i32
+    }
+}
+
 pub type FileName = String;
 
 pub struct FileLines {
diff --git a/src/libsyntax/ext/asm.rs b/src/libsyntax/ext/asm.rs
index f82fe4b13a2..702be0c0eee 100644
--- a/src/libsyntax/ext/asm.rs
+++ b/src/libsyntax/ext/asm.rs
@@ -199,7 +199,7 @@ pub fn expand_asm<'cx>(cx: &'cx mut ExtCtxt, sp: Span, tts: &[ast::TokenTree])
         }
     }
 
-    let codemap::ExpnId(expn_id) = cx.codemap().record_expansion(codemap::ExpnInfo {
+    let expn_id = cx.codemap().record_expansion(codemap::ExpnInfo {
         call_site: sp,
         callee: codemap::NameAndSpan {
             name: "asm".to_string(),
diff --git a/src/libsyntax/lib.rs b/src/libsyntax/lib.rs
index 7a504d22c1e..a4271544146 100644
--- a/src/libsyntax/lib.rs
+++ b/src/libsyntax/lib.rs
@@ -33,6 +33,7 @@ extern crate debug;
 #[phase(plugin, link)] extern crate log;
 extern crate serialize;
 extern crate term;
+extern crate libc;
 
 pub mod util {
     pub mod interner;