resolved conflict with upstream commit

3 files changed, 9 insertions, 6 deletions

diff --git a/src/libsyntax_ext/concat_idents.rs b/src/libsyntax_ext/concat_idents.rs
index 544b1410d3d..b8345e7cf40 100644
--- a/src/libsyntax_ext/concat_idents.rs
+++ b/src/libsyntax_ext/concat_idents.rs
@@ -31,6 +31,11 @@ pub fn expand_syntax_ext<'cx>(cx: &'cx mut ExtCtxt,
         return base::DummyResult::expr(sp);
     }
 
+    if tts.is_empty() {
+        cx.span_err(sp, "concat_idents! takes 1 or more arguments.");
+        return DummyResult::expr(sp);
+    }
+
     let mut res_str = String::new();
     for (i, e) in tts.iter().enumerate() {
         if i & 1 == 1 {
diff --git a/src/libsyntax_ext/deriving/custom.rs b/src/libsyntax_ext/deriving/custom.rs
index 5fd5e299488..76da1746a03 100644
--- a/src/libsyntax_ext/deriving/custom.rs
+++ b/src/libsyntax_ext/deriving/custom.rs
@@ -22,11 +22,9 @@ struct MarkAttrs<'a>(&'a [ast::Name]);
 
 impl<'a> Visitor<'a> for MarkAttrs<'a> {
     fn visit_attribute(&mut self, attr: &Attribute) {
-        if let Some(name) = attr.name() {
-            if self.0.contains(&name) {
-                mark_used(attr);
-                mark_known(attr);
-            }
+        if self.0.contains(&attr.name()) {
+            mark_used(attr);
+            mark_known(attr);
         }
     }
 
diff --git a/src/libsyntax_ext/deriving/generic/mod.rs b/src/libsyntax_ext/deriving/generic/mod.rs
index becd70149fd..80f65957c39 100644
--- a/src/libsyntax_ext/deriving/generic/mod.rs
+++ b/src/libsyntax_ext/deriving/generic/mod.rs
@@ -472,7 +472,7 @@ impl<'a> TraitDef<'a> {
                 attrs.extend(item.attrs
                     .iter()
                     .filter(|a| {
-                        a.name().is_some() && match &*a.name().unwrap().as_str() {
+                        match &*a.name().as_str() {
                             "allow" | "warn" | "deny" | "forbid" | "stable" | "unstable" => true,
                             _ => false,
                         }