Make sure feature gate errors are recoverable (take 2)

Author: petrochenkov

src/librustc/ty/mod.rs

@@ -2839,16 +2839,14 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             self.impl_polarity(def_id1) == self.impl_polarity(def_id2)
                 && trait1_is_empty
                 && trait2_is_empty
-        } else if self.features().marker_trait_attr {
+        } else {
             let is_marker_impl = |def_id: DefId| -> bool {
                 let trait_ref = self.impl_trait_ref(def_id);
                 trait_ref.map_or(false, |tr| self.trait_def(tr.def_id).is_marker)
             };
             self.impl_polarity(def_id1) == self.impl_polarity(def_id2)
                 && is_marker_impl(def_id1)
                 && is_marker_impl(def_id2)
-        } else {
-            false
         };
 
         if is_legit {

src/librustc_driver/driver.rs

@@ -1098,23 +1098,20 @@ where
         ast_validation::check_crate(sess, &krate)
     });
 
-    time(sess, "name resolution", || -> CompileResult {
+    time(sess, "name resolution", || {
         resolver.resolve_crate(&krate);
-        Ok(())
-    })?;
+    });
 
     // Needs to go *after* expansion to be able to check the results of macro expansion.
     time(sess, "complete gated feature checking", || {
-        sess.track_errors(|| {
-            syntax::feature_gate::check_crate(
-                &krate,
-                &sess.parse_sess,
-                &sess.features_untracked(),
-                &attributes,
-                sess.opts.unstable_features,
-            );
-        })
-    })?;
+        syntax::feature_gate::check_crate(
+            &krate,
+            &sess.parse_sess,
+            &sess.features_untracked(),
+            &attributes,
+            sess.opts.unstable_features,
+        );
+    });
 
     // Lower ast -> hir.
     // First, we need to collect the dep_graph.

src/test/ui/conditional-compilation/cfg-attr-crate-2.rs

@@ -1,8 +1,8 @@
-//
-// compile-flags: --cfg broken
-
 // https://github.com/rust-lang/rust/issues/21833#issuecomment-72353044
 
+// compile-flags: --cfg broken
+
+#![crate_type = "lib"]
 #![cfg_attr(broken, no_core)] //~ ERROR no_core is experimental
 
-fn main() { }
+pub struct S {}

src/test/ui/conditional-compilation/cfg-attr-multi-invalid-1.rs

@@ -1,7 +1,7 @@
-//
 // compile-flags: --cfg broken
 
 #![feature(cfg_attr_multi)]
+#![crate_type = "lib"]
 #![cfg_attr(broken, no_core, no_std)] //~ ERROR no_core is experimental
 
-fn main() { }
+pub struct S {}

src/test/ui/conditional-compilation/cfg-attr-multi-invalid-2.rs

@@ -1,7 +1,7 @@
-//
 // compile-flags: --cfg broken
 
 #![feature(cfg_attr_multi)]
+#![crate_type = "lib"]
 #![cfg_attr(broken, no_std, no_core)] //~ ERROR no_core is experimental
 
-fn main() { }
+pub struct S {}

src/test/ui/feature-gates/feature-gate-alloc-error-handler.rs

@@ -9,3 +9,6 @@ use core::alloc::Layout;
 fn oom(info: Layout) -> ! {
     loop {}
 }
+
+#[panic_handler]
+fn panic(_: &core::panic::PanicInfo) -> ! { loop {} }

src/test/ui/feature-gates/feature-gate-allow_fail.rs

@@ -5,3 +5,4 @@ fn ok_to_fail() {
     assert!(false);
 }
 
+fn main() {}

src/test/ui/feature-gates/feature-gate-async-await-2015-edition.rs

@@ -6,5 +6,5 @@ async fn foo() {} //~ ERROR async fn is unstable
 
 fn main() {
     let _ = async {}; //~ ERROR cannot find struct, variant or union type `async`
-    let _ = async || {}; //~ ERROR cannot find value `async` in this scope
+    let _ = async || { true }; //~ ERROR cannot find value `async` in this scope
 }

src/test/ui/feature-gates/feature-gate-async-await-2015-edition.stderr

@@ -7,7 +7,7 @@ LL |     let _ = async {}; //~ ERROR cannot find struct, variant or union type `
 error[E0425]: cannot find value `async` in this scope
   --> $DIR/feature-gate-async-await-2015-edition.rs:9:13
    |
-LL |     let _ = async || {}; //~ ERROR cannot find value `async` in this scope
+LL |     let _ = async || { true }; //~ ERROR cannot find value `async` in this scope
    |             ^^^^^ not found in this scope
 
 error[E0658]: async fn is unstable (see issue #50547)

src/test/ui/feature-gates/feature-gate-const_fn.rs

@@ -9,14 +9,16 @@ trait Foo {
                                 //~| ERROR trait fns cannot be declared const
 }
 
-impl Foo {
-    const fn baz() -> u32 { 0 } // ok
-}
-
 impl Foo for u32 {
     const fn foo() -> u32 { 0 } //~ ERROR trait fns cannot be declared const
 }
 
+trait Bar {}
+
+impl dyn Bar {
+    const fn baz() -> u32 { 0 } // ok
+}
+
 static FOO: usize = foo();
 const BAR: usize = foo();
 

src/test/ui/feature-gates/feature-gate-const_fn.stderr

@@ -11,7 +11,7 @@ LL |     const fn bar() -> u32 { 0 } //~ ERROR const fn is unstable
    |     ^^^^^ trait fns cannot be const
 
 error[E0379]: trait fns cannot be declared const
-  --> $DIR/feature-gate-const_fn.rs:17:5
+  --> $DIR/feature-gate-const_fn.rs:13:5
    |
 LL |     const fn foo() -> u32 { 0 } //~ ERROR trait fns cannot be declared const
    |     ^^^^^ trait fns cannot be const

src/test/ui/feature-gates/feature-gate-doc_keyword.rs

@@ -1,3 +1,5 @@
 #[doc(keyword = "match")] //~ ERROR: #[doc(keyword = "...")] is experimental
 /// wonderful
 mod foo{}
+
+fn main() {}

src/test/ui/feature-gates/feature-gate-dropck-ugeh.rs

@@ -1,14 +1,11 @@
 // gate-test-dropck_parametricity
 
 // Ensure that attempts to use the unsafe attribute are feature-gated.
-
 // Example adapted from RFC 1238 text (just left out the feature gate).
 
 // https://github.com/rust-lang/rfcs/blob/master/text/1238-nonparametric-dropck.md
 //     #example-of-the-unguarded-escape-hatch
 
-// #![feature(dropck_parametricity)]
-
 use std::cell::Cell;
 
 struct Concrete<'a>(u32, Cell<Option<&'a Concrete<'a>>>);
@@ -18,6 +15,7 @@ struct Foo<T> { data: Vec<T> }
 impl<T> Drop for Foo<T> {
     #[unsafe_destructor_blind_to_params] // This is the UGEH attribute
     //~^ ERROR unsafe_destructor_blind_to_params has been replaced
+    //~| WARN use of deprecated attribute `dropck_parametricity`
     fn drop(&mut self) { }
 }
 
@@ -29,4 +27,3 @@ fn main() {
     foo.data[0].1.set(Some(&foo.data[1]));
     foo.data[1].1.set(Some(&foo.data[0]));
 }
-

src/test/ui/feature-gates/feature-gate-dropck-ugeh.stderr

@@ -1,11 +1,19 @@
 error[E0658]: unsafe_destructor_blind_to_params has been replaced by may_dangle and will be removed in the future (see issue #28498)
-  --> $DIR/feature-gate-dropck-ugeh.rs:19:5
+  --> $DIR/feature-gate-dropck-ugeh.rs:16:5
    |
 LL |     #[unsafe_destructor_blind_to_params] // This is the UGEH attribute
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: add #![feature(dropck_parametricity)] to the crate attributes to enable
 
+warning: use of deprecated attribute `dropck_parametricity`: unsafe_destructor_blind_to_params has been replaced by may_dangle and will be removed in the future. See https://github.com/rust-lang/rust/issues/34761
+  --> $DIR/feature-gate-dropck-ugeh.rs:16:5
+   |
+LL |     #[unsafe_destructor_blind_to_params] // This is the UGEH attribute
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace this attribute with `#[may_dangle]`
+   |
+   = note: #[warn(deprecated)] on by default
+
 error: aborting due to previous error
 
 For more information about this error, try `rustc --explain E0658`.

src/test/ui/feature-gates/feature-gate-existential-type.rs

@@ -1,15 +1,17 @@
 // Check that existential types must be ungated to use the `existential` keyword
 
-
-
 existential type Foo: std::fmt::Debug; //~ ERROR existential types are unstable
 
 trait Bar {
     type Baa: std::fmt::Debug;
+    fn define() -> Self::Baa;
 }
 
 impl Bar for () {
     existential type Baa: std::fmt::Debug; //~ ERROR existential types are unstable
+    fn define() -> Self::Baa { 0 }
 }
 
+fn define() -> Foo { 0 }
+
 fn main() {}

src/test/ui/feature-gates/feature-gate-existential-type.stderr

@@ -1,13 +1,13 @@
 error[E0658]: existential types are unstable (see issue #34511)
-  --> $DIR/feature-gate-existential-type.rs:5:1
+  --> $DIR/feature-gate-existential-type.rs:3:1
    |
 LL | existential type Foo: std::fmt::Debug; //~ ERROR existential types are unstable
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: add #![feature(existential_type)] to the crate attributes to enable
 
 error[E0658]: existential types are unstable (see issue #34511)
-  --> $DIR/feature-gate-existential-type.rs:12:5
+  --> $DIR/feature-gate-existential-type.rs:11:5
    |
 LL |     existential type Baa: std::fmt::Debug; //~ ERROR existential types are unstable
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

src/test/ui/feature-gates/feature-gate-generators.rs

@@ -1,3 +1,4 @@
 fn main() {
     yield true; //~ ERROR yield syntax is experimental
+                //~^ ERROR yield statement outside of generator literal
 }

src/test/ui/feature-gates/feature-gate-generators.stderr

@@ -6,6 +6,13 @@ LL |     yield true; //~ ERROR yield syntax is experimental
    |
    = help: add #![feature(generators)] to the crate attributes to enable
 
-error: aborting due to previous error
+error[E0627]: yield statement outside of generator literal
+  --> $DIR/feature-gate-generators.rs:2:5
+   |
+LL |     yield true; //~ ERROR yield syntax is experimental
+   |     ^^^^^^^^^^
+
+error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0658`.
+Some errors occurred: E0627, E0658.
+For more information about an error, try `rustc --explain E0627`.

src/test/ui/feature-gates/feature-gate-generic_associated_types.rs

@@ -11,9 +11,9 @@ trait PointerFamily<U> {
 struct Foo;
 
 impl PointerFamily<u32> for Foo {
-    type Pointer<usize> = Box<usize>;
+    type Pointer<Usize> = Box<Usize>;
     //~^ ERROR generic associated types are unstable
-    type Pointer2<u32> = Box<u32>;
+    type Pointer2<U32> = Box<U32>;
     //~^ ERROR generic associated types are unstable
 }
 

src/test/ui/feature-gates/feature-gate-generic_associated_types.stderr

@@ -25,15 +25,15 @@ LL |     type Pointer2<T>: Deref<Target = T> where T: Clone, U: Clone;
 error[E0658]: generic associated types are unstable (see issue #44265)
   --> $DIR/feature-gate-generic_associated_types.rs:14:5
    |
-LL |     type Pointer<usize> = Box<usize>;
+LL |     type Pointer<Usize> = Box<Usize>;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: add #![feature(generic_associated_types)] to the crate attributes to enable
 
 error[E0658]: generic associated types are unstable (see issue #44265)
   --> $DIR/feature-gate-generic_associated_types.rs:16:5
    |
-LL |     type Pointer2<u32> = Box<u32>;
+LL |     type Pointer2<U32> = Box<U32>;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: add #![feature(generic_associated_types)] to the crate attributes to enable

src/test/ui/feature-gates/feature-gate-intrinsics.rs

@@ -1,9 +1,7 @@
 extern "rust-intrinsic" {   //~ ERROR intrinsics are subject to change
-    fn bar();
+    fn bar(); //~ ERROR unrecognized intrinsic function: `bar`
 }
 
-extern "rust-intrinsic" fn baz() {  //~ ERROR intrinsics are subject to change
-}
+extern "rust-intrinsic" fn baz() {} //~ ERROR intrinsics are subject to change
 
-fn main() {
-}
+fn main() {}

src/test/ui/feature-gates/feature-gate-intrinsics.stderr

@@ -2,7 +2,7 @@ error[E0658]: intrinsics are subject to change
   --> $DIR/feature-gate-intrinsics.rs:1:1
    |
 LL | / extern "rust-intrinsic" {   //~ ERROR intrinsics are subject to change
-LL | |     fn bar();
+LL | |     fn bar(); //~ ERROR unrecognized intrinsic function: `bar`
 LL | | }
    | |_^
    |
@@ -11,12 +11,18 @@ LL | | }
 error[E0658]: intrinsics are subject to change
   --> $DIR/feature-gate-intrinsics.rs:5:1
    |
-LL | / extern "rust-intrinsic" fn baz() {  //~ ERROR intrinsics are subject to change
-LL | | }
-   | |_^
+LL | extern "rust-intrinsic" fn baz() {} //~ ERROR intrinsics are subject to change
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: add #![feature(intrinsics)] to the crate attributes to enable
 
-error: aborting due to 2 previous errors
+error[E0093]: unrecognized intrinsic function: `bar`
+  --> $DIR/feature-gate-intrinsics.rs:2:5
+   |
+LL |     fn bar(); //~ ERROR unrecognized intrinsic function: `bar`
+   |     ^^^^^^^^^ unrecognized intrinsic
+
+error: aborting due to 3 previous errors
 
-For more information about this error, try `rustc --explain E0658`.
+Some errors occurred: E0093, E0658.
+For more information about an error, try `rustc --explain E0093`.

src/test/ui/feature-gates/feature-gate-lang-items.rs

@@ -1,5 +1,5 @@
-#[lang="foo"]   //~ ERROR language items are subject to change
+#[lang = "foo"] //~ ERROR language items are subject to change
+                //~^ ERROR definition of an unknown language item: `foo`
 trait Foo {}
 
-fn main() {
-}
+fn main() {}

src/test/ui/feature-gates/feature-gate-lang-items.stderr

@@ -1,11 +1,18 @@
 error[E0658]: language items are subject to change
   --> $DIR/feature-gate-lang-items.rs:1:1
    |
-LL | #[lang="foo"]   //~ ERROR language items are subject to change
-   | ^^^^^^^^^^^^^
+LL | #[lang = "foo"] //~ ERROR language items are subject to change
+   | ^^^^^^^^^^^^^^^
    |
    = help: add #![feature(lang_items)] to the crate attributes to enable
 
-error: aborting due to previous error
+error[E0522]: definition of an unknown language item: `foo`
+  --> $DIR/feature-gate-lang-items.rs:1:1
+   |
+LL | #[lang = "foo"] //~ ERROR language items are subject to change
+   | ^^^^^^^^^^^^^^^ definition of unknown language item `foo`
+
+error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0658`.
+Some errors occurred: E0522, E0658.
+For more information about an error, try `rustc --explain E0522`.

src/test/ui/feature-gates/feature-gate-linkage.rs

@@ -2,3 +2,5 @@ extern {
     #[linkage = "extern_weak"] static foo: isize;
     //~^ ERROR: the `linkage` attribute is experimental and not portable
 }
+
+fn main() {}

src/test/ui/feature-gates/feature-gate-may-dangle.rs

@@ -3,7 +3,9 @@
 // Check that `may_dangle` is rejected if `dropck_eyepatch` feature gate is absent.
 
 struct Pt<A>(A);
-impl<#[may_dangle] A> Drop for Pt<A> {
+unsafe impl<#[may_dangle] A> Drop for Pt<A> {
     //~^ ERROR may_dangle has unstable semantics and may be removed in the future
     fn drop(&mut self) { }
 }
+
+fn main() {}

src/test/ui/feature-gates/feature-gate-may-dangle.stderr

@@ -1,8 +1,8 @@
 error[E0658]: may_dangle has unstable semantics and may be removed in the future (see issue #34761)
-  --> $DIR/feature-gate-may-dangle.rs:6:6
+  --> $DIR/feature-gate-may-dangle.rs:6:13
    |
-LL | impl<#[may_dangle] A> Drop for Pt<A> {
-   |      ^^^^^^^^^^^^^
+LL | unsafe impl<#[may_dangle] A> Drop for Pt<A> {
+   |             ^^^^^^^^^^^^^
    |
    = help: add #![feature(dropck_eyepatch)] to the crate attributes to enable