3 files changed, 11 insertions, 17 deletions
diff --git a/src/libsyntax_ext/deriving/clone.rs b/src/libsyntax_ext/deriving/clone.rs
index eb7d480aa98..67ef69babdc 100644
--- a/src/libsyntax_ext/deriving/clone.rs
+++ b/src/libsyntax_ext/deriving/clone.rs
@@ -174,14 +174,12 @@ fn cs_clone(name: &str,
             all_fields = af;
             vdata = &variant.data;
         }
-        EnumNonMatchingCollapsed(..) => {
-            cx.span_bug(trait_span,
-                        &format!("non-matching enum variants in \
-                                 `derive({})`",
-                                 name))
-        }
+        EnumNonMatchingCollapsed(..) => cx.span_bug(trait_span, &format!(
+            "non-matching enum variants in `derive({})`",
+            name,
+        )),
         StaticEnum(..) | StaticStruct(..) => {
-            cx.span_bug(trait_span, &format!("static method in `derive({})`", name))
+            cx.span_bug(trait_span, &format!("associated function in `derive({})`", name))
         }
     }
 
@@ -191,12 +189,10 @@ fn cs_clone(name: &str,
                 .map(|field| {
                     let ident = match field.name {
                         Some(i) => i,
-                        None => {
-                            cx.span_bug(trait_span,
-                                        &format!("unnamed field in normal struct in \
-                                                `derive({})`",
-                                                    name))
-                        }
+                        None => cx.span_bug(trait_span, &format!(
+                            "unnamed field in normal struct in `derive({})`",
+                            name,
+                        )),
                     };
                     let call = subcall(cx, field);
                     cx.field_imm(field.span, ident, call)
diff --git a/src/libsyntax_ext/deriving/default.rs b/src/libsyntax_ext/deriving/default.rs
index 6176791c31b..cfc0f3cd6cb 100644
--- a/src/libsyntax_ext/deriving/default.rs
+++ b/src/libsyntax_ext/deriving/default.rs
@@ -75,6 +75,6 @@ fn default_substructure(cx: &mut ExtCtxt<'_>,
             // let compilation continue
             DummyResult::raw_expr(trait_span, true)
         }
-        _ => cx.span_bug(trait_span, "Non-static method in `derive(Default)`"),
+        _ => cx.span_bug(trait_span, "method in `derive(Default)`"),
     };
 }
diff --git a/src/libsyntax_ext/deriving/generic/mod.rs b/src/libsyntax_ext/deriving/generic/mod.rs
index 1886a5154b7..fd2c1552d32 100644
--- a/src/libsyntax_ext/deriving/generic/mod.rs
+++ b/src/libsyntax_ext/deriving/generic/mod.rs
@@ -1055,9 +1055,7 @@ impl<'a> MethodDef<'a> {
                 })
                 .collect()
         } else {
-            cx.span_bug(trait_.span,
-                        "no self arguments to non-static method in generic \
-                         `derive`")
+            cx.span_bug(trait_.span, "no self arguments for method in generic `derive`")
         };
 
         // body of the inner most destructuring match