Point macros 1.1 errors to the input item

src/libsyntax_ext/deriving/custom.rs

@@ -10,12 +10,14 @@
 
 use std::panic;
 
+use errors::FatalError;
 use rustc_macro::{TokenStream, __internal};
 use syntax::ast::{self, ItemKind};
-use syntax::codemap::Span;
+use syntax::codemap::{ExpnInfo, MacroAttribute, NameAndSpan, Span};
 use syntax::ext::base::*;
 use syntax::fold::{self, Folder};
-use errors::FatalError;
+use syntax::parse::token::intern;
+use syntax::print::pprust;
 
 pub struct CustomDerive {
     inner: fn(TokenStream) -> TokenStream,
@@ -31,7 +33,7 @@ impl MultiItemModifier for CustomDerive {
     fn expand(&self,
               ecx: &mut ExtCtxt,
               span: Span,
-              _meta_item: &ast::MetaItem,
+              meta_item: &ast::MetaItem,
               item: Annotatable)
               -> Vec<Annotatable> {
         let item = match item {
@@ -53,6 +55,17 @@ impl MultiItemModifier for CustomDerive {
             }
         }
 
+        let input_span = Span {
+            expn_id: ecx.codemap().record_expansion(ExpnInfo {
+                call_site: span,
+                callee: NameAndSpan {
+                    format: MacroAttribute(intern(&pprust::meta_item_to_string(meta_item))),
+                    span: Some(span),
+                    allow_internal_unstable: true,
+                },
+            }),
+            ..item.span
+        };
         let input = __internal::new_token_stream(item);
         let res = __internal::set_parse_sess(&ecx.parse_sess, || {
             let inner = self.inner;
@@ -77,9 +90,9 @@ impl MultiItemModifier for CustomDerive {
 
         // Right now we have no knowledge of spans at all in custom derive
         // macros, everything is just parsed as a string. Reassign all spans to
-        // the #[derive] attribute for better errors here.
+        // the input `item` for better errors here.
         item.into_iter().flat_map(|item| {
-            ChangeSpan { span: span }.fold_item(item)
+            ChangeSpan { span: input_span }.fold_item(item)
         }).map(Annotatable::Item).collect()
     }
 }

src/test/compile-fail-fulldeps/rustc-macro/append-impl.rs

@@ -23,8 +23,8 @@ trait Append {
 #[derive(PartialEq,
          Append,
          Eq)]
-//~^^ ERROR: the semantics of constant patterns is not yet settled
 struct A {
+//~^ ERROR: the semantics of constant patterns is not yet settled
     inner: u32,
 }
 

src/test/compile-fail-fulldeps/rustc-macro/expand-to-unstable-2.rs

@@ -17,8 +17,8 @@
 extern crate derive_unstable_2;
 
 #[derive(Unstable)]
-//~^ ERROR: reserved for internal compiler
 struct A;
+//~^ ERROR: reserved for internal compiler
 
 fn main() {
     foo();

src/test/compile-fail-fulldeps/rustc-macro/expand-to-unstable.rs

@@ -17,8 +17,8 @@
 extern crate derive_unstable;
 
 #[derive(Unstable)]
-//~^ ERROR: use of unstable library feature
 struct A;
+//~^ ERROR: use of unstable library feature
 
 fn main() {
     unsafe { foo(); }