diff --git a/src/librustc_metadata/diagnostics.rs b/src/librustc_metadata/diagnostics.rs
index f52e1437acc..c03375bf825 100644
--- a/src/librustc_metadata/diagnostics.rs
+++ b/src/librustc_metadata/diagnostics.rs
@@ -98,10 +98,10 @@ Erroneous code examples:
 
 ```compile_fail,E0466
 #[macro_use(a_macro(another_macro))] // error: invalid import declaration
-extern crate some_crate;
+extern crate core as some_crate;
 
 #[macro_use(i_want = "some_macros")] // error: invalid import declaration
-extern crate another_crate;
+extern crate core as another_crate;
 ```
 
 This is a syntax error at the level of attribute declarations. The proper
@@ -135,10 +135,10 @@ Erroneous code examples:
 
 ```compile_fail,E0467
 #[macro_reexport]                    // error: no macros listed for export
-extern crate macros_for_good;
+extern crate core as macros_for_good;
 
 #[macro_reexport(fun_macro = "foo")] // error: not a macro identifier
-extern crate other_macros_for_good;
+extern crate core as other_macros_for_good;
 ```
 
 This is a syntax error at the level of attribute declarations.
@@ -165,8 +165,8 @@ Example of erroneous code:
 ```compile_fail,E0468
 mod foo {
     #[macro_use(helpful_macro)] // error: must be at crate root to import
-    extern crate some_crate;    //        macros from another crate
-    helpful_macro!(...)
+    extern crate core;          //        macros from another crate
+    helpful_macro!(...);
 }
 ```
 
diff --git a/src/test/codegen-units/item-collection/overloaded-operators.rs b/src/test/codegen-units/item-collection/overloaded-operators.rs
index c275eb954b0..0295311334b 100644
--- a/src/test/codegen-units/item-collection/overloaded-operators.rs
+++ b/src/test/codegen-units/item-collection/overloaded-operators.rs
@@ -45,8 +45,8 @@ impl IndexMut<usize> for Indexable {
 }
 
 
-//~ TRANS_ITEM fn overloaded_operators::{{impl}}[2]::eq[0]
-//~ TRANS_ITEM fn overloaded_operators::{{impl}}[2]::ne[0]
+//~ TRANS_ITEM fn overloaded_operators::{{impl}}[4]::eq[0]
+//~ TRANS_ITEM fn overloaded_operators::{{impl}}[4]::ne[0]
 #[derive(PartialEq)]
 pub struct Equatable(u32);
 
@@ -54,7 +54,7 @@ pub struct Equatable(u32);
 impl Add<u32> for Equatable {
     type Output = u32;
 
-    //~ TRANS_ITEM fn overloaded_operators::{{impl}}[3]::add[0]
+    //~ TRANS_ITEM fn overloaded_operators::{{impl}}[2]::add[0]
     fn add(self, rhs: u32) -> u32 {
         self.0 + rhs
     }
@@ -63,7 +63,7 @@ impl Add<u32> for Equatable {
 impl Deref for Equatable {
     type Target = u32;
 
-    //~ TRANS_ITEM fn overloaded_operators::{{impl}}[4]::deref[0]
+    //~ TRANS_ITEM fn overloaded_operators::{{impl}}[3]::deref[0]
     fn deref(&self) -> &Self::Target {
         &self.0
     }
diff --git a/src/test/compile-fail-fulldeps/derive-no-std-not-supported.rs b/src/test/compile-fail-fulldeps/derive-no-std-not-supported.rs
index 01c81a8bbce..6ae5544d686 100644
--- a/src/test/compile-fail-fulldeps/derive-no-std-not-supported.rs
+++ b/src/test/compile-fail-fulldeps/derive-no-std-not-supported.rs
@@ -10,7 +10,6 @@
 
 #![no_std]
 
-extern crate core;
 extern crate rand;
 extern crate serialize as rustc_serialize;
 
diff --git a/src/test/compile-fail/gated-non-ascii-idents.rs b/src/test/compile-fail/gated-non-ascii-idents.rs
index f4b9830d579..9e042c3a7d5 100644
--- a/src/test/compile-fail/gated-non-ascii-idents.rs
+++ b/src/test/compile-fail/gated-non-ascii-idents.rs
@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-extern crate bäz; //~ ERROR non-ascii idents
+extern crate core as bäz; //~ ERROR non-ascii idents
 
 use föö::bar; //~ ERROR non-ascii idents
 
diff --git a/src/test/compile-fail/self_type_keyword.rs b/src/test/compile-fail/self_type_keyword.rs
index b9c9d7a389b..1622378a71c 100644
--- a/src/test/compile-fail/self_type_keyword.rs
+++ b/src/test/compile-fail/self_type_keyword.rs
@@ -39,11 +39,17 @@ pub fn main() {
     }
 }
 
-use std::option::Option as Self;
-//~^ ERROR expected identifier, found keyword `Self`
+mod m1 {
+    extern crate core as Self;
+    //~^ ERROR expected identifier, found keyword `Self`
+}
 
-extern crate Self;
-//~^ ERROR expected identifier, found keyword `Self`
+mod m2 {
+    use std::option::Option as Self;
+    //~^ ERROR expected identifier, found keyword `Self`
+}
 
-trait Self {}
-//~^ ERROR expected identifier, found keyword `Self`
+mod m3 {
+    trait Self {}
+    //~^ ERROR expected identifier, found keyword `Self`
+}