Rollup of 5 pull requests

appveyor.yml

@@ -126,6 +126,8 @@ clone_depth: 2
 build: false
 
 install:
+  # Print which AppVeyor agent version we're running on.
+  - appveyor version
   # If we need to download a custom MinGW, do so here and set the path
   # appropriately.
   #

src/librustc/infer/error_reporting/nice_region_error/named_anon_conflict.rs

@@ -1,6 +1,7 @@
 //! Error Reporting for Anonymous Region Lifetime Errors
 //! where one region is named and the other is anonymous.
 use crate::infer::error_reporting::nice_region_error::NiceRegionError;
+use crate::hir::{FunctionRetTy, TyKind};
 use crate::ty;
 use errors::{Applicability, DiagnosticBuilder};
 
@@ -11,9 +12,10 @@ impl<'a, 'gcx, 'tcx> NiceRegionError<'a, 'gcx, 'tcx> {
         let (span, sub, sup) = self.get_regions();
 
         debug!(
-            "try_report_named_anon_conflict(sub={:?}, sup={:?})",
+            "try_report_named_anon_conflict(sub={:?}, sup={:?}, error={:?})",
             sub,
-            sup
+            sup,
+            self.error,
         );
 
         // Determine whether the sub and sup consist of one named region ('a)
@@ -84,6 +86,13 @@ impl<'a, 'gcx, 'tcx> NiceRegionError<'a, 'gcx, 'tcx> {
             {
                 return None;
             }
+            if let FunctionRetTy::Return(ty) = &fndecl.output {
+                if let (TyKind::Def(_, _), ty::ReStatic) = (&ty.node, sub) {
+                    // This is an impl Trait return that evaluates de need of 'static.
+                    // We handle this case better in `static_impl_trait`.
+                    return None;
+                }
+            }
         }
 
         let (error_var, span_label_var) = if let Some(simple_ident) = arg.pat.simple_ident() {
@@ -103,13 +112,13 @@ impl<'a, 'gcx, 'tcx> NiceRegionError<'a, 'gcx, 'tcx> {
             error_var
         );
 
+        diag.span_label(span, format!("lifetime `{}` required", named));
         diag.span_suggestion(
-                new_ty_span,
-                &format!("add explicit lifetime `{}` to {}", named, span_label_var),
-                new_ty.to_string(),
-                Applicability::Unspecified,
-            )
-            .span_label(span, format!("lifetime `{}` required", named));
+            new_ty_span,
+            &format!("add explicit lifetime `{}` to {}", named, span_label_var),
+            new_ty.to_string(),
+            Applicability::Unspecified,
+        );
 
         Some(diag)
     }

src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs

@@ -132,6 +132,15 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             }
         });
         if let Some(i) = best_choice {
+            if let Some(next) = categorized_path.get(i + 1) {
+                if categorized_path[i].0 == ConstraintCategory::Return
+                    && next.0 == ConstraintCategory::OpaqueType
+                {
+                    // The return expression is being influenced by the return type being
+                    // impl Trait, point at the return type and not the return expr.
+                    return *next;
+                }
+            }
             return categorized_path[i];
         }
 
@@ -240,6 +249,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             self.provides_universal_region(r, fr, outlived_fr)
         });
 
+        debug!("report_error: category={:?} {:?}", category, span);
         // Check if we can use one of the "nice region errors".
         if let (Some(f), Some(o)) = (self.to_error_region(fr), self.to_error_region(outlived_fr)) {
             let tables = infcx.tcx.typeck_tables_of(mir_def_id);

src/librustc_mir/interpret/snapshot.rs

@@ -431,7 +431,7 @@ impl<'a, 'mir, 'tcx> Eq for EvalSnapshot<'a, 'mir, 'tcx>
 impl<'a, 'mir, 'tcx> PartialEq for EvalSnapshot<'a, 'mir, 'tcx>
 {
     fn eq(&self, other: &Self) -> bool {
-        // FIXME: This looks to be a *ridicolously expensive* comparison operation.
+        // FIXME: This looks to be a *ridiculously expensive* comparison operation.
         // Doesn't this make tons of copies?  Either `snapshot` is very badly named,
         // or it does!
         self.snapshot() == other.snapshot()

src/libsyntax/parse/parser.rs

@@ -6722,6 +6722,22 @@ impl<'a> Parser<'a> {
             self.expect(&token::OpenDelim(token::Brace))?;
             let mut trait_items = vec![];
             while !self.eat(&token::CloseDelim(token::Brace)) {
+                if let token::DocComment(_) = self.token {
+                    if self.look_ahead(1,
+                    |tok| tok == &token::Token::CloseDelim(token::Brace)) {
+                        let mut err = self.diagnostic().struct_span_err_with_code(
+                            self.span,
+                            "found a documentation comment that doesn't document anything",
+                            DiagnosticId::Error("E0584".into()),
+                        );
+                        err.help("doc comments must come before what they document, maybe a \
+                            comment was intended with `//`?",
+                        );
+                        err.emit();
+                        self.bump();
+                        continue;
+                    }
+                }
                 let mut at_end = false;
                 match self.parse_trait_item(&mut at_end) {
                     Ok(item) => trait_items.push(item),

src/test/ui/impl-trait/must_outlive_least_region_or_bound.rs

@@ -1,7 +1,7 @@
 use std::fmt::Debug;
 
 fn elided(x: &i32) -> impl Copy { x }
-//~^ ERROR explicit lifetime required in the type of `x` [E0621]
+//~^ ERROR cannot infer an appropriate lifetime
 
 fn explicit<'a>(x: &'a i32) -> impl Copy { x }
 //~^ ERROR cannot infer an appropriate lifetime

src/test/ui/impl-trait/must_outlive_least_region_or_bound.stderr

@@ -1,10 +1,20 @@
-error[E0621]: explicit lifetime required in the type of `x`
-  --> $DIR/must_outlive_least_region_or_bound.rs:3:23
+error: cannot infer an appropriate lifetime
+  --> $DIR/must_outlive_least_region_or_bound.rs:3:35
    |
 LL | fn elided(x: &i32) -> impl Copy { x }
-   |              ----     ^^^^^^^^^ lifetime `'static` required
-   |              |
-   |              help: add explicit lifetime `'static` to the type of `x`: `&'static i32`
+   |                       ---------   ^ ...but this borrow...
+   |                       |
+   |                       this return type evaluates to the `'static` lifetime...
+   |
+note: ...can't outlive the anonymous lifetime #1 defined on the function body at 3:1
+  --> $DIR/must_outlive_least_region_or_bound.rs:3:1
+   |
+LL | fn elided(x: &i32) -> impl Copy { x }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+help: you can add a constraint to the return type to make it last less than `'static` and match the anonymous lifetime #1 defined on the function body at 3:1
+   |
+LL | fn elided(x: &i32) -> impl Copy + '_ { x }
+   |                       ^^^^^^^^^^^^^^
 
 error: cannot infer an appropriate lifetime
   --> $DIR/must_outlive_least_region_or_bound.rs:6:44
@@ -67,5 +77,5 @@ LL | fn ty_param_wont_outlive_static<T:Debug>(x: T) -> impl Debug + 'static {
 
 error: aborting due to 5 previous errors
 
-Some errors occurred: E0310, E0621, E0623.
+Some errors occurred: E0310, E0623.
 For more information about an error, try `rustc --explain E0310`.

src/test/ui/nll/ty-outlives/impl-trait-captures.rs

@@ -8,8 +8,8 @@ trait Foo<'a> {
 impl<'a, T> Foo<'a> for T { }
 
 fn foo<'a, T>(x: &T) -> impl Foo<'a> {
+//~^ ERROR explicit lifetime required in the type of `x` [E0621]
     x
-        //~^ ERROR explicit lifetime required in the type of `x` [E0621]
 }
 
 fn main() {}

src/test/ui/nll/ty-outlives/impl-trait-captures.stderr

@@ -1,8 +1,8 @@
 error[E0621]: explicit lifetime required in the type of `x`
-  --> $DIR/impl-trait-captures.rs:11:5
+  --> $DIR/impl-trait-captures.rs:10:25
    |
-LL |     x
-   |     ^ lifetime `ReEarlyBound(0, 'a)` required
+LL | fn foo<'a, T>(x: &T) -> impl Foo<'a> {
+   |                         ^^^^^^^^^^^^ lifetime `ReEarlyBound(0, 'a)` required
 help: add explicit lifetime `ReEarlyBound(0, 'a)` to the type of `x`
    |
 LL | fn foo<'a, T>(x: &ReEarlyBound(0, 'a) T) -> impl Foo<'a> {

src/test/ui/parser/doc-inside-trait-item.rs

@@ -0,0 +1,6 @@
+trait User{
+    fn test();
+    /// empty doc
+    //~^ ERROR found a documentation comment that doesn't document anything
+}
+fn main() {}

src/test/ui/parser/doc-inside-trait-item.stderr

@@ -0,0 +1,11 @@
+error[E0584]: found a documentation comment that doesn't document anything
+  --> $DIR/doc-inside-trait-item.rs:3:5
+   |
+LL |     /// empty doc
+   |     ^^^^^^^^^^^^^
+   |
+   = help: doc comments must come before what they document, maybe a comment was intended with `//`?
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0584`.

src/tools/cargotest/main.rs

@@ -30,7 +30,7 @@ const TEST_REPOS: &'static [Test] = &[
     },
     Test {
         name: "tokei",
-        repo: "https://github.com/Aaronepower/tokei",
+        repo: "https://github.com/XAMPPRocky/tokei",
         sha: "5e11c4852fe4aa086b0e4fe5885822fbe57ba928",
         lock: None,
         packages: &[],