diff --git a/src/librustc/driver/session.rs b/src/librustc/driver/session.rs
index 50f61f8f06a..946aa62f91c 100644
--- a/src/librustc/driver/session.rs
+++ b/src/librustc/driver/session.rs
@@ -28,7 +28,8 @@ use syntax::{ast, codemap};
 use std::os;
 use std::cell::{Cell, RefCell};
 
-
+// Represents the data associated with a compilation
+// session for a single crate.
 pub struct Session {
     pub targ_cfg: config::Config,
     pub opts: config::Options,
diff --git a/src/librustc/metadata/encoder.rs b/src/librustc/metadata/encoder.rs
index fbf0288418a..7c4eda6dd71 100644
--- a/src/librustc/metadata/encoder.rs
+++ b/src/librustc/metadata/encoder.rs
@@ -1584,37 +1584,25 @@ fn encode_plugin_registrar_fn(ecx: &EncodeContext, ebml_w: &mut Encoder) {
     }
 }
 
-struct MacroDefVisitor<'a, 'b, 'c> {
-    ecx: &'a EncodeContext<'b>,
-    ebml_w: &'a mut Encoder<'c>
+/// Given a span, write the text of that span into the output stream
+/// as an exported macro
+fn encode_macro_def(ecx: &EncodeContext,
+                    ebml_w: &mut Encoder,
+                    span: &syntax::codemap::Span) {
+    let def = ecx.tcx.sess.codemap().span_to_snippet(*span)
+        .expect("Unable to find source for macro");
+    ebml_w.start_tag(tag_macro_def);
+    ebml_w.wr_str(def.as_slice());
+    ebml_w.end_tag();
 }
 
-impl<'a, 'b, 'c> Visitor<()> for MacroDefVisitor<'a, 'b, 'c> {
-    fn visit_item(&mut self, item: &Item, _: ()) {
-        match item.node {
-            ItemMac(..) => {
-                let def = self.ecx.tcx.sess.codemap().span_to_snippet(item.span)
-                    .expect("Unable to find source for macro");
-                self.ebml_w.start_tag(tag_macro_def);
-                self.ebml_w.wr_str(def.as_slice());
-                self.ebml_w.end_tag();
-            }
-            _ => {}
-        }
-        visit::walk_item(self, item, ());
-    }
-}
-
-fn encode_macro_defs<'a>(ecx: &'a EncodeContext,
-                         krate: &Crate,
-                         ebml_w: &'a mut Encoder) {
+/// Serialize the text of the exported macros
+fn encode_macro_defs(ecx: &EncodeContext,
+                     krate: &Crate,
+                     ebml_w: &mut Encoder) {
     ebml_w.start_tag(tag_exported_macros);
-    {
-        let mut visitor = MacroDefVisitor {
-            ecx: ecx,
-            ebml_w: ebml_w,
-        };
-        visit::walk_crate(&mut visitor, krate, ());
+    for span in krate.exported_macros.iter() {
+        encode_macro_def(ecx, ebml_w, span);
     }
     ebml_w.end_tag();
 }
diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index ebfc45d22ce..4a48d3f7028 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -249,6 +249,7 @@ pub struct Crate {
     pub attrs: Vec<Attribute>,
     pub config: CrateConfig,
     pub span: Span,
+    pub exported_macros: Vec<Span>
 }
 
 pub type MetaItem = Spanned<MetaItem_>;
@@ -1245,6 +1246,7 @@ mod test {
                 hi: BytePos(20),
                 expn_info: None,
             },
+            exported_macros: Vec::new(),
         };
         // doesn't matter which encoder we use....
         let _f = &e as &serialize::Encodable<json::Encoder, io::IoError>;
diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index 7ff680497bf..dcb69ae8f7e 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -410,6 +410,7 @@ pub struct ExtCtxt<'a> {
 
     pub mod_path: Vec<ast::Ident> ,
     pub trace_mac: bool,
+    pub exported_macros: Vec<codemap::Span>
 }
 
 impl<'a> ExtCtxt<'a> {
@@ -421,7 +422,8 @@ impl<'a> ExtCtxt<'a> {
             backtrace: None,
             mod_path: Vec::new(),
             ecfg: ecfg,
-            trace_mac: false
+            trace_mac: false,
+            exported_macros: Vec::new(),
         }
     }
 
@@ -539,6 +541,9 @@ impl<'a> ExtCtxt<'a> {
     pub fn name_of(&self, st: &str) -> ast::Name {
         token::intern(st)
     }
+    pub fn push_exported_macro(&mut self, span: codemap::Span) {
+        self.exported_macros.push(span);
+    }
 }
 
 /// Extract a string literal from the macro expanded version of `expr`,
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index b7d72ae4deb..e8a78e85d89 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -518,10 +518,9 @@ fn expand_item_mac(it: Gc<ast::Item>, fld: &mut MacroExpander)
             // create issue to recommend refactoring here?
             fld.extsbox.insert(intern(name.as_slice()), ext);
             if attr::contains_name(it.attrs.as_slice(), "macro_export") {
-                SmallVector::one(it)
-            } else {
-                SmallVector::zero()
+                fld.cx.push_exported_macro(it.span);
             }
+            SmallVector::zero()
         }
         None => {
             match expanded.make_items() {
@@ -1039,6 +1038,7 @@ pub struct ExportedMacros {
 
 pub fn expand_crate(parse_sess: &parse::ParseSess,
                     cfg: ExpansionConfig,
+                    // these are the macros being imported to this crate:
                     macros: Vec<ExportedMacros>,
                     user_exts: Vec<NamedSyntaxExtension>,
                     c: Crate) -> Crate {
@@ -1066,7 +1066,8 @@ pub fn expand_crate(parse_sess: &parse::ParseSess,
         expander.extsbox.insert(name, extension);
     }
 
-    let ret = expander.fold_crate(c);
+    let mut ret = expander.fold_crate(c);
+    ret.exported_macros = expander.cx.exported_macros.clone();
     parse_sess.span_diagnostic.handler().abort_if_errors();
     return ret;
 }
diff --git a/src/libsyntax/fold.rs b/src/libsyntax/fold.rs
index bcdf920e5dd..f7cb1ae1934 100644
--- a/src/libsyntax/fold.rs
+++ b/src/libsyntax/fold.rs
@@ -713,6 +713,7 @@ pub fn noop_fold_crate<T: Folder>(c: Crate, folder: &mut T) -> Crate {
         attrs: c.attrs.iter().map(|x| folder.fold_attribute(*x)).collect(),
         config: c.config.iter().map(|x| fold_meta_item_(*x, folder)).collect(),
         span: folder.new_span(c.span),
+        exported_macros: c.exported_macros.iter().map(|sp| folder.new_span(*sp)).collect(),
     }
 }
 
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 743eeed9da5..84db2bc5a22 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -5386,7 +5386,8 @@ impl<'a> Parser<'a> {
             module: m,
             attrs: inner,
             config: self.cfg.clone(),
-            span: mk_sp(lo, self.span.lo)
+            span: mk_sp(lo, self.span.lo),
+            exported_macros: Vec::new(),
         }
     }