Rollup of 11 pull requests

src/libcore/future.rs

@@ -45,18 +45,18 @@ pub trait Future {
     ///
     /// This function returns:
     ///
-    /// - `Poll::Pending` if the future is not ready yet
-    /// - `Poll::Ready(val)` with the result `val` of this future if it finished
-    /// successfully.
+    /// - [`Poll::Pending`] if the future is not ready yet
+    /// - [`Poll::Ready(val)`] with the result `val` of this future if it
+    ///   finished successfully.
     ///
     /// Once a future has finished, clients should not `poll` it again.
     ///
     /// When a future is not ready yet, `poll` returns
-    /// [`Poll::Pending`](::task::Poll). The future will *also* register the
+    /// `Poll::Pending`. The future will *also* register the
     /// interest of the current task in the value being produced. For example,
     /// if the future represents the availability of data on a socket, then the
     /// task is recorded so that when data arrives, it is woken up (via
-    /// [`cx.waker()`](::task::Context::waker)). Once a task has been woken up,
+    /// [`cx.waker()`]). Once a task has been woken up,
     /// it should attempt to `poll` the future again, which may or may not
     /// produce a final value.
     ///
@@ -90,6 +90,10 @@ pub trait Future {
     /// then any future calls to `poll` may panic, block forever, or otherwise
     /// cause bad behavior. The `Future` trait itself provides no guarantees
     /// about the behavior of `poll` after a future has completed.
+    ///
+    /// [`Poll::Pending`]: ../task/enum.Poll.html#variant.Pending
+    /// [`Poll::Ready(val)`]: ../task/enum.Poll.html#variant.Ready
+    /// [`cx.waker()`]: ../task/struct.Context.html#method.waker
     fn poll(self: PinMut<Self>, cx: &mut task::Context) -> Poll<Self::Output>;
 }
 

src/libproc_macro/diagnostic.rs

@@ -97,7 +97,7 @@ impl Diagnostic {
     /// Emit the diagnostic.
     #[unstable(feature = "proc_macro", issue = "38356")]
     pub fn emit(self) {
-        ::__internal::with_sess(move |(sess, _)| {
+        ::__internal::with_sess(move |sess, _| {
             let handler = &sess.span_diagnostic;
             let level = __internal::level_to_internal_level(self.level);
             let mut diag = rustc::DiagnosticBuilder::new(handler, level, &*self.message);

src/libproc_macro/lib.rs

@@ -58,8 +58,7 @@ use syntax::parse::{self, token};
 use syntax::symbol::{keywords, Symbol};
 use syntax::tokenstream;
 use syntax::parse::lexer::{self, comments};
-use syntax_pos::{FileMap, Pos, SyntaxContext, FileName};
-use syntax_pos::hygiene::Mark;
+use syntax_pos::{FileMap, Pos, FileName};
 
 /// The main type provided by this crate, representing an abstract stream of
 /// tokens, or, more specifically, a sequence of token trees.
@@ -109,6 +108,7 @@ impl TokenStream {
 /// Attempts to break the string into tokens and parse those tokens into a token stream.
 /// May fail for a number of reasons, for example, if the string contains unbalanced delimiters
 /// or characters not existing in the language.
+/// All tokens in the parsed stream get `Span::call_site()` spans.
 ///
 /// NOTE: Some errors may cause panics instead of returning `LexError`. We reserve the right to
 /// change these errors into `LexError`s later.
@@ -117,17 +117,10 @@ impl FromStr for TokenStream {
     type Err = LexError;
 
     fn from_str(src: &str) -> Result<TokenStream, LexError> {
-        __internal::with_sess(|(sess, mark)| {
-            let src = src.to_string();
-            let name = FileName::ProcMacroSourceCode;
-            let expn_info = mark.expn_info().unwrap();
-            let call_site = expn_info.call_site;
-            // notify the expansion info that it is unhygienic
-            let mark = Mark::fresh(mark);
-            mark.set_expn_info(expn_info);
-            let span = call_site.with_ctxt(SyntaxContext::empty().apply_mark(mark));
-            let stream = parse::parse_stream_from_source_str(name, src, sess, Some(span));
-            Ok(__internal::token_stream_wrap(stream))
+        __internal::with_sess(|sess, data| {
+            Ok(__internal::token_stream_wrap(parse::parse_stream_from_source_str(
+                FileName::ProcMacroSourceCode, src.to_string(), sess, Some(data.call_site.0)
+            )))
         })
     }
 }
@@ -184,8 +177,6 @@ impl iter::FromIterator<TokenStream> for TokenStream {
 #[unstable(feature = "proc_macro", issue = "38356")]
 pub mod token_stream {
     use syntax::tokenstream;
-    use syntax_pos::DUMMY_SP;
-
     use {TokenTree, TokenStream, Delimiter};
 
     /// An iterator over `TokenStream`'s `TokenTree`s.
@@ -214,7 +205,7 @@ pub mod token_stream {
                 // need to flattened during iteration over stream's token trees.
                 // Eventually this needs to be removed in favor of keeping original token trees
                 // and not doing the roundtrip through AST.
-                if tree.span().0 == DUMMY_SP {
+                if tree.span().0.is_dummy() {
                     if let TokenTree::Group(ref group) = tree {
                         if group.delimiter() == Delimiter::None {
                             self.cursor.insert(group.stream.clone().0);
@@ -284,10 +275,7 @@ impl Span {
     /// A span that resolves at the macro definition site.
     #[unstable(feature = "proc_macro", issue = "38356")]
     pub fn def_site() -> Span {
-        ::__internal::with_sess(|(_, mark)| {
-            let call_site = mark.expn_info().unwrap().call_site;
-            Span(call_site.with_ctxt(SyntaxContext::empty().apply_mark(mark)))
-        })
+        ::__internal::with_sess(|_, data| data.def_site)
     }
 
     /// The span of the invocation of the current procedural macro.
@@ -296,7 +284,7 @@ impl Span {
     /// at the macro call site will be able to refer to them as well.
     #[unstable(feature = "proc_macro", issue = "38356")]
     pub fn call_site() -> Span {
-        ::__internal::with_sess(|(_, mark)| Span(mark.expn_info().unwrap().call_site))
+        ::__internal::with_sess(|_, data| data.call_site)
     }
 
     /// The original source file into which this span points.
@@ -1243,7 +1231,7 @@ impl TokenTree {
             }
 
             Interpolated(_) => {
-                __internal::with_sess(|(sess, _)| {
+                __internal::with_sess(|sess, _| {
                     let tts = token.interpolated_to_tokenstream(sess, span);
                     tt!(Group::new(Delimiter::None, TokenStream(tts)))
                 })
@@ -1354,20 +1342,21 @@ pub mod __internal {
     pub use quote::{LiteralKind, SpannedSymbol, Quoter, unquote};
 
     use std::cell::Cell;
+    use std::ptr;
 
     use syntax::ast;
     use syntax::ext::base::ExtCtxt;
-    use syntax::ext::hygiene::Mark;
     use syntax::ptr::P;
     use syntax::parse::{self, ParseSess};
     use syntax::parse::token::{self, Token};
     use syntax::tokenstream;
     use syntax_pos::{BytePos, Loc, DUMMY_SP};
+    use syntax_pos::hygiene::{Mark, SyntaxContext, Transparency};
 
-    use super::{TokenStream, LexError};
+    use super::{TokenStream, LexError, Span};
 
     pub fn lookup_char_pos(pos: BytePos) -> Loc {
-        with_sess(|(sess, _)| sess.codemap().lookup_char_pos(pos))
+        with_sess(|sess, _| sess.codemap().lookup_char_pos(pos))
     }
 
     pub fn new_token_stream(item: P<ast::Item>) -> TokenStream {
@@ -1380,7 +1369,7 @@ pub mod __internal {
     }
 
     pub fn token_stream_parse_items(stream: TokenStream) -> Result<Vec<P<ast::Item>>, LexError> {
-        with_sess(move |(sess, _)| {
+        with_sess(move |sess, _| {
             let mut parser = parse::stream_to_parser(sess, stream.0);
             let mut items = Vec::new();
 
@@ -1411,16 +1400,30 @@ pub mod __internal {
                                     expand: fn(TokenStream) -> TokenStream);
     }
 
+    #[derive(Clone, Copy)]
+    pub struct ProcMacroData {
+        pub def_site: Span,
+        pub call_site: Span,
+    }
+
+    #[derive(Clone, Copy)]
+    struct ProcMacroSess {
+        parse_sess: *const ParseSess,
+        data: ProcMacroData,
+    }
+
     // Emulate scoped_thread_local!() here essentially
     thread_local! {
-        static CURRENT_SESS: Cell<(*const ParseSess, Mark)> =
-            Cell::new((0 as *const _, Mark::root()));
+        static CURRENT_SESS: Cell<ProcMacroSess> = Cell::new(ProcMacroSess {
+            parse_sess: ptr::null(),
+            data: ProcMacroData { def_site: Span(DUMMY_SP), call_site: Span(DUMMY_SP) },
+        });
     }
 
     pub fn set_sess<F, R>(cx: &ExtCtxt, f: F) -> R
         where F: FnOnce() -> R
     {
-        struct Reset { prev: (*const ParseSess, Mark) }
+        struct Reset { prev: ProcMacroSess }
 
         impl Drop for Reset {
             fn drop(&mut self) {
@@ -1430,24 +1433,42 @@ pub mod __internal {
 
         CURRENT_SESS.with(|p| {
             let _reset = Reset { prev: p.get() };
-            p.set((cx.parse_sess, cx.current_expansion.mark));
+
+            // No way to determine def location for a proc macro right now, so use call location.
+            let location = cx.current_expansion.mark.expn_info().unwrap().call_site;
+            // Opaque mark was already created by expansion, now create its transparent twin.
+            // We can't use the call-site span literally here, even if it appears to provide
+            // correct name resolution, because it has all the `ExpnInfo` wrong, so the edition
+            // checks, lint macro checks, macro backtraces will all break.
+            let opaque_mark = cx.current_expansion.mark;
+            let transparent_mark = Mark::fresh_cloned(opaque_mark);
+            transparent_mark.set_transparency(Transparency::Transparent);
+
+            let to_span = |mark| Span(location.with_ctxt(SyntaxContext::empty().apply_mark(mark)));
+            p.set(ProcMacroSess {
+                parse_sess: cx.parse_sess,
+                data: ProcMacroData {
+                    def_site: to_span(opaque_mark),
+                    call_site: to_span(transparent_mark),
+                },
+            });
             f()
         })
     }
 
     pub fn in_sess() -> bool
     {
-        let p = CURRENT_SESS.with(|p| p.get());
-        !p.0.is_null()
+        !CURRENT_SESS.with(|sess| sess.get()).parse_sess.is_null()
     }
 
     pub fn with_sess<F, R>(f: F) -> R
-        where F: FnOnce((&ParseSess, Mark)) -> R
+        where F: FnOnce(&ParseSess, &ProcMacroData) -> R
     {
-        let p = CURRENT_SESS.with(|p| p.get());
-        assert!(!p.0.is_null(), "proc_macro::__internal::with_sess() called \
-                                 before set_parse_sess()!");
-        f(unsafe { (&*p.0, p.1) })
+        let sess = CURRENT_SESS.with(|sess| sess.get());
+        if sess.parse_sess.is_null() {
+            panic!("procedural macro API is used outside of a procedural macro");
+        }
+        f(unsafe { &*sess.parse_sess }, &sess.data)
     }
 }
 

src/librustc/hir/map/definitions.rs

@@ -486,12 +486,7 @@ impl Definitions {
     #[inline]
     pub fn opt_span(&self, def_id: DefId) -> Option<Span> {
         if def_id.krate == LOCAL_CRATE {
-            let span = self.def_index_to_span.get(&def_id.index).cloned().unwrap_or(DUMMY_SP);
-            if span != DUMMY_SP {
-                Some(span)
-            } else {
-                None
-            }
+            self.def_index_to_span.get(&def_id.index).cloned()
         } else {
             None
         }
@@ -588,8 +583,8 @@ impl Definitions {
             self.opaque_expansions_that_defined.insert(index, expansion);
         }
 
-        // The span is added if it isn't DUMMY_SP
-        if span != DUMMY_SP {
+        // The span is added if it isn't dummy
+        if !span.is_dummy() {
             self.def_index_to_span.insert(index, span);
         }
 

src/librustc/hir/map/mod.rs

@@ -25,7 +25,7 @@ use rustc_target::spec::abi::Abi;
 use syntax::ast::{self, Name, NodeId, CRATE_NODE_ID};
 use syntax::codemap::Spanned;
 use syntax::ext::base::MacroKind;
-use syntax_pos::Span;
+use syntax_pos::{Span, DUMMY_SP};
 
 use hir::*;
 use hir::print::Nested;
@@ -664,6 +664,33 @@ impl<'hir> Map<'hir> {
         self.as_local_node_id(id).map(|id| self.get(id)) // read recorded by `get`
     }
 
+    pub fn get_generics(&self, id: DefId) -> Option<&'hir Generics> {
+        self.get_if_local(id).and_then(|node| {
+            match node {
+                NodeImplItem(ref impl_item) => Some(&impl_item.generics),
+                NodeTraitItem(ref trait_item) => Some(&trait_item.generics),
+                NodeItem(ref item) => {
+                    match item.node {
+                        ItemFn(_, _, ref generics, _) |
+                        ItemTy(_, ref generics) |
+                        ItemEnum(_, ref generics) |
+                        ItemStruct(_, ref generics) |
+                        ItemUnion(_, ref generics) |
+                        ItemTrait(_, _, ref generics, ..) |
+                        ItemTraitAlias(ref generics, _) |
+                        ItemImpl(_, _, _, ref generics, ..) => Some(generics),
+                        _ => None,
+                    }
+                }
+                _ => None,
+            }
+        })
+    }
+
+    pub fn get_generics_span(&self, id: DefId) -> Option<Span> {
+        self.get_generics(id).map(|generics| generics.span).filter(|sp| *sp != DUMMY_SP)
+    }
+
     /// Retrieve the Node corresponding to `id`, returning None if
     /// cannot be found.
     pub fn find(&self, id: NodeId) -> Option<Node<'hir>> {

src/librustc/hir/mod.rs

@@ -31,7 +31,7 @@ use hir::def_id::{DefId, DefIndex, LocalDefId, CRATE_DEF_INDEX};
 use util::nodemap::{NodeMap, FxHashSet};
 use mir::mono::Linkage;
 
-use syntax_pos::{Span, DUMMY_SP};
+use syntax_pos::{Span, DUMMY_SP, symbol::InternedString};
 use syntax::codemap::{self, Spanned};
 use rustc_target::spec::abi::Abi;
 use syntax::ast::{self, CrateSugar, Ident, Name, NodeId, DUMMY_NODE_ID, AsmDialect};
@@ -547,6 +547,15 @@ impl Generics {
 
         own_counts
     }
+
+    pub fn get_named(&self, name: &InternedString) -> Option<&GenericParam> {
+        for param in &self.params {
+            if *name == param.name.ident().as_interned_str() {
+                return Some(param);
+            }
+        }
+        None
+    }
 }
 
 /// Synthetic Type Parameters are converted to an other form during lowering, this allows

src/librustc/infer/error_reporting/mod.rs

@@ -189,6 +189,8 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         self,
         region: ty::Region<'tcx>,
     ) -> (String, Option<Span>) {
+        let cm = self.sess.codemap();
+
         let scope = region.free_region_binding_scope(self);
         let node = self.hir.as_local_node_id(scope).unwrap_or(DUMMY_NODE_ID);
         let unknown;
@@ -219,10 +221,26 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             }
         };
         let (prefix, span) = match *region {
-            ty::ReEarlyBound(ref br) => (
-                format!("the lifetime {} as defined on", br.name),
-                self.sess.codemap().def_span(self.hir.span(node)),
-            ),
+            ty::ReEarlyBound(ref br) => {
+                let mut sp = cm.def_span(self.hir.span(node));
+                if let Some(param) = self.hir.get_generics(scope).and_then(|generics| {
+                    generics.get_named(&br.name)
+                }) {
+                    sp = param.span;
+                }
+                (format!("the lifetime {} as defined on", br.name), sp)
+            }
+            ty::ReFree(ty::FreeRegion {
+                bound_region: ty::BoundRegion::BrNamed(_, ref name), ..
+            }) => {
+                let mut sp = cm.def_span(self.hir.span(node));
+                if let Some(param) = self.hir.get_generics(scope).and_then(|generics| {
+                    generics.get_named(&name)
+                }) {
+                    sp = param.span;
+                }
+                (format!("the lifetime {} as defined on", name), sp)
+            }
             ty::ReFree(ref fr) => match fr.bound_region {
                 ty::BrAnon(idx) => (
                     format!("the anonymous lifetime #{} defined on", idx + 1),
@@ -234,7 +252,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
                 ),
                 _ => (
                     format!("the lifetime {} as defined on", fr.bound_region),
-                    self.sess.codemap().def_span(self.hir.span(node)),
+                    cm.def_span(self.hir.span(node)),
                 ),
             },
             _ => bug!(),