make emit_feature_err take a ParseSess

src/librustc/middle/stability.rs

@@ -411,8 +411,8 @@ impl<'a, 'tcx> Checker<'a, 'tcx> {
                                                &feature, &r),
                         None => format!("use of unstable library feature '{}'", &feature)
                     };
-                    emit_feature_err(&self.tcx.sess.parse_sess.span_diagnostic,
+                    emit_feature_err(&self.tcx.sess.parse_sess, &feature, span,
-                                      &feature, span, GateIssue::Library(Some(issue)), &msg);
+                                     GateIssue::Library(Some(issue)), &msg);
                 }
             }
             Some(&Stability { ref level, ref feature, .. }) => {

src/librustc_passes/static_recursion.rs

@@ -143,7 +143,7 @@ impl<'a, 'ast: 'a> CheckItemRecursionVisitor<'a, 'ast> {
             });
             if any_static {
                 if !self.sess.features.borrow().static_recursion {
-                    emit_feature_err(&self.sess.parse_sess.span_diagnostic,
+                    emit_feature_err(&self.sess.parse_sess,
                                      "static_recursion",
                                      *self.root_span,
                                      GateIssue::Language,

src/librustc_typeck/astconv.rs

@@ -795,7 +795,7 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
                 // For now, require that parenthetical notation be used
                 // only with `Fn()` etc.
                 if !self.tcx().sess.features.borrow().unboxed_closures && trait_def.paren_sugar {
-                    emit_feature_err(&self.tcx().sess.parse_sess.span_diagnostic,
+                    emit_feature_err(&self.tcx().sess.parse_sess,
                                      "unboxed_closures", span, GateIssue::Language,
                                      "\
                         the precise format of `Fn`-family traits' \
@@ -807,7 +807,7 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
                 // For now, require that parenthetical notation be used
                 // only with `Fn()` etc.
                 if !self.tcx().sess.features.borrow().unboxed_closures && !trait_def.paren_sugar {
-                    emit_feature_err(&self.tcx().sess.parse_sess.span_diagnostic,
+                    emit_feature_err(&self.tcx().sess.parse_sess,
                                      "unboxed_closures", span, GateIssue::Language,
                                      "\
                         parenthetical notation is only stable when used with `Fn`-family traits");

src/librustc_typeck/check/mod.rs

@@ -3256,7 +3256,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
         if let Some((def_id, variant)) = variant {
             if variant.kind == ty::VariantKind::Tuple &&
                     !self.tcx.sess.features.borrow().relaxed_adts {
-                emit_feature_err(&self.tcx.sess.parse_sess.span_diagnostic,
+                emit_feature_err(&self.tcx.sess.parse_sess,
                                  "relaxed_adts", span, GateIssue::Language,
                                  "tuple structs and variants in struct patterns are unstable");
             }

src/libsyntax/config.rs

@@ -157,7 +157,7 @@ impl<'a> StripUnconfigured<'a> {
         // flag the offending attributes
         for attr in attrs.iter() {
             if !self.features.map(|features| features.stmt_expr_attributes).unwrap_or(true) {
-                emit_feature_err(&self.sess.span_diagnostic,
+                emit_feature_err(&self.sess,
                                  "stmt_expr_attributes",
                                  attr.span,
                                  GateIssue::Language,

src/libsyntax/ext/expand.rs

@@ -344,7 +344,7 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
         // Detect use of feature-gated or invalid attributes on macro invoations
         // since they will not be detected after macro expansion.
         for attr in attrs.iter() {
-            feature_gate::check_attribute(&attr, &self.cx.parse_sess.span_diagnostic,
+            feature_gate::check_attribute(&attr, &self.cx.parse_sess,
                                           &self.cx.parse_sess.codemap(),
                                           &self.cx.ecfg.features.unwrap());
         }

src/libsyntax/feature_gate.rs

@@ -679,16 +679,15 @@ impl GatedCfg {
     pub fn check_and_emit(&self, sess: &ParseSess, features: &Features) {
         let (cfg, feature, has_feature) = GATED_CFGS[self.index];
         if !has_feature(features) && !sess.codemap().span_allows_unstable(self.span) {
-            let diagnostic = &sess.span_diagnostic;
             let explain = format!("`cfg({})` is experimental and subject to change", cfg);
-            emit_feature_err(diagnostic, feature, self.span, GateIssue::Language, &explain);
+            emit_feature_err(sess, feature, self.span, GateIssue::Language, &explain);
         }
     }
 }
 
 struct Context<'a> {
     features: &'a Features,
-    span_handler: &'a Handler,
+    parse_sess: &'a ParseSess,
     cm: &'a CodeMap,
     plugin_attributes: &'a [(String, AttributeType)],
 }
@@ -699,7 +698,7 @@ macro_rules! gate_feature_fn {
         let has_feature: bool = has_feature(&$cx.features);
         debug!("gate_feature(feature = {:?}, span = {:?}); has? {}", name, span, has_feature);
         if !has_feature && !cx.cm.span_allows_unstable(span) {
-            emit_feature_err(cx.span_handler, name, span, GateIssue::Language, explain);
+            emit_feature_err(cx.parse_sess, name, span, GateIssue::Language, explain);
         }
     }}
 }
@@ -756,10 +755,10 @@ impl<'a> Context<'a> {
     }
 }
 
-pub fn check_attribute(attr: &ast::Attribute, handler: &Handler,
+pub fn check_attribute(attr: &ast::Attribute, parse_sess: &ParseSess,
                        cm: &CodeMap, features: &Features) {
     let cx = Context {
-        features: features, span_handler: handler,
+        features: features, parse_sess: parse_sess,
         cm: cm, plugin_attributes: &[]
     };
     cx.check_attribute(attr, true);
@@ -788,8 +787,10 @@ pub enum GateIssue {
     Library(Option<u32>)
 }
 
-pub fn emit_feature_err(diag: &Handler, feature: &str, span: Span, issue: GateIssue,
+pub fn emit_feature_err(sess: &ParseSess, feature: &str, span: Span, issue: GateIssue,
                         explain: &str) {
+    let diag = &sess.span_diagnostic;
+
     let issue = match issue {
         GateIssue::Language => find_lang_feature_issue(feature),
         GateIssue::Library(lib) => lib,
@@ -962,9 +963,10 @@ impl<'a> Visitor for PostExpansionVisitor<'a> {
                 if attr::contains_name(&i.attrs[..], "simd") {
                     gate_feature_post!(&self, simd, i.span,
                                        "SIMD types are experimental and possibly buggy");
-                    self.context.span_handler.span_warn(i.span,
+                    self.context.parse_sess.span_diagnostic.span_warn(i.span,
-                                                        "the `#[simd]` attribute is deprecated, \
+                                                                      "the `#[simd]` attribute \
-                                                         use `#[repr(simd)]` instead");
+                                                                       is deprecated, use \
+                                                                       `#[repr(simd)]` instead");
                 }
                 for attr in &i.attrs {
                     if attr.name() == "repr" {
@@ -1273,7 +1275,7 @@ pub fn check_crate(krate: &ast::Crate,
     maybe_stage_features(&sess.span_diagnostic, krate, unstable);
     let ctx = Context {
         features: features,
-        span_handler: &sess.span_diagnostic,
+        parse_sess: sess,
         cm: sess.codemap(),
         plugin_attributes: plugin_attributes,
     };

src/libsyntax_ext/asm.rs

@@ -53,7 +53,7 @@ pub fn expand_asm<'cx>(cx: &'cx mut ExtCtxt,
                        tts: &[tokenstream::TokenTree])
                        -> Box<base::MacResult + 'cx> {
     if !cx.ecfg.enable_asm() {
-        feature_gate::emit_feature_err(&cx.parse_sess.span_diagnostic,
+        feature_gate::emit_feature_err(&cx.parse_sess,
                                        "asm",
                                        sp,
                                        feature_gate::GateIssue::Language,

src/libsyntax_ext/concat_idents.rs

@@ -23,7 +23,7 @@ pub fn expand_syntax_ext<'cx>(cx: &'cx mut ExtCtxt,
                               tts: &[TokenTree])
                               -> Box<base::MacResult + 'cx> {
     if !cx.ecfg.enable_concat_idents() {
-        feature_gate::emit_feature_err(&cx.parse_sess.span_diagnostic,
+        feature_gate::emit_feature_err(&cx.parse_sess,
                                        "concat_idents",
                                        sp,
                                        feature_gate::GateIssue::Language,

src/libsyntax_ext/deriving/mod.rs

@@ -221,7 +221,7 @@ pub fn expand_derive(cx: &mut ExtCtxt,
         // the old custom derive mechanism. If the feature isn't enabled, we
         // issue an error, otherwise manufacture the `derive_Foo` attribute.
         } else if !cx.ecfg.enable_custom_derive() {
-            feature_gate::emit_feature_err(&cx.parse_sess.span_diagnostic,
+            feature_gate::emit_feature_err(&cx.parse_sess,
                                            "custom_derive",
                                            titem.span,
                                            feature_gate::GateIssue::Language,

src/libsyntax_ext/log_syntax.rs

@@ -19,7 +19,7 @@ pub fn expand_syntax_ext<'cx>(cx: &'cx mut base::ExtCtxt,
                               tts: &[tokenstream::TokenTree])
                               -> Box<base::MacResult + 'cx> {
     if !cx.ecfg.enable_log_syntax() {
-        feature_gate::emit_feature_err(&cx.parse_sess.span_diagnostic,
+        feature_gate::emit_feature_err(&cx.parse_sess,
                                        "log_syntax",
                                        sp,
                                        feature_gate::GateIssue::Language,

src/libsyntax_ext/trace_macros.rs

@@ -20,7 +20,7 @@ pub fn expand_trace_macros(cx: &mut ExtCtxt,
                            tt: &[TokenTree])
                            -> Box<base::MacResult + 'static> {
     if !cx.ecfg.enable_trace_macros() {
-        feature_gate::emit_feature_err(&cx.parse_sess.span_diagnostic,
+        feature_gate::emit_feature_err(&cx.parse_sess,
                                        "trace_macros",
                                        sp,
                                        feature_gate::GateIssue::Language,