Resolve incorrect diagnostic for using a non-const value in a constant

13 files changed, 47 insertions, 57 deletions

diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index 365ba974d5a..0d1f6328105 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -4164,6 +4164,9 @@ impl<'a> Resolver<'a> {
                 span_bug!(span, "unexpected {:?} in bindings", def)
             }
             Def::Local(node_id) => {
+                use ResolutionError::*;
+                let mut res_err = None;
+
                 for rib in ribs {
                     match rib.kind {
                         NormalRibKind | ModuleRibKind(..) | MacroDefinition(..) |
@@ -4199,21 +4202,26 @@ impl<'a> Resolver<'a> {
                             // named function item. This is not allowed, so we
                             // report an error.
                             if record_used {
-                                resolve_error(self, span,
-                                    ResolutionError::CannotCaptureDynamicEnvironmentInFnItem);
+                                // We don't immediately trigger a resolve error, because
+                                // we want certain other resolution errors (namely those
+                                // emitted for `ConstantItemRibKind` below) to take
+                                // precedence.
+                                res_err = Some(CannotCaptureDynamicEnvironmentInFnItem);
                             }
-                            return Def::Err;
                         }
                         ConstantItemRibKind => {
                             // Still doesn't deal with upvars
                             if record_used {
-                                resolve_error(self, span,
-                                    ResolutionError::AttemptToUseNonConstantValueInConstant);
+                                resolve_error(self, span, AttemptToUseNonConstantValueInConstant);
                             }
                             return Def::Err;
                         }
                     }
                 }
+                if let Some(res_err) = res_err {
+                     resolve_error(self, span, res_err);
+                     return Def::Err;
+                }
             }
             Def::TyParam(..) | Def::SelfTy(..) => {
                 for rib in ribs {
diff --git a/src/test/ui/impl-trait/bindings.rs b/src/test/ui/impl-trait/bindings.rs
index 899303646d6..91d092634a9 100644
--- a/src/test/ui/impl-trait/bindings.rs
+++ b/src/test/ui/impl-trait/bindings.rs
@@ -2,27 +2,27 @@
 
 fn a<T: Clone>(x: T) {
     const foo: impl Clone = x;
-//~^ ERROR can't capture dynamic environment in a fn item
+    //~^ ERROR attempt to use a non-constant value in a constant
 }
 
 fn b<T: Clone>(x: T) {
     let _ = move || {
         const foo: impl Clone = x;
-//~^ ERROR can't capture dynamic environment in a fn item
+        //~^ ERROR attempt to use a non-constant value in a constant
     };
 }
 
 trait Foo<T: Clone> {
     fn a(x: T) {
         const foo: impl Clone = x;
-//~^ ERROR can't capture dynamic environment in a fn item
+        //~^ ERROR attempt to use a non-constant value in a constant
     }
 }
 
 impl<T: Clone> Foo<T> for i32 {
     fn a(x: T) {
         const foo: impl Clone = x;
-//~^ ERROR can't capture dynamic environment in a fn item
+        //~^ ERROR attempt to use a non-constant value in a constant
     }
 }
 
diff --git a/src/test/ui/impl-trait/bindings.stderr b/src/test/ui/impl-trait/bindings.stderr
index 2a9be7a270a..a5bf583afea 100644
--- a/src/test/ui/impl-trait/bindings.stderr
+++ b/src/test/ui/impl-trait/bindings.stderr
@@ -1,35 +1,27 @@
-error[E0434]: can't capture dynamic environment in a fn item
+error[E0435]: attempt to use a non-constant value in a constant
   --> $DIR/bindings.rs:4:29
    |
 LL |     const foo: impl Clone = x;
-   |                             ^
-   |
-   = help: use the `|| { ... }` closure form instead
+   |                             ^ non-constant value
 
-error[E0434]: can't capture dynamic environment in a fn item
+error[E0435]: attempt to use a non-constant value in a constant
   --> $DIR/bindings.rs:10:33
    |
 LL |         const foo: impl Clone = x;
-   |                                 ^
-   |
-   = help: use the `|| { ... }` closure form instead
+   |                                 ^ non-constant value
 
-error[E0434]: can't capture dynamic environment in a fn item
+error[E0435]: attempt to use a non-constant value in a constant
   --> $DIR/bindings.rs:17:33
    |
 LL |         const foo: impl Clone = x;
-   |                                 ^
-   |
-   = help: use the `|| { ... }` closure form instead
+   |                                 ^ non-constant value
 
-error[E0434]: can't capture dynamic environment in a fn item
+error[E0435]: attempt to use a non-constant value in a constant
   --> $DIR/bindings.rs:24:33
    |
 LL |         const foo: impl Clone = x;
-   |                                 ^
-   |
-   = help: use the `|| { ... }` closure form instead
+   |                                 ^ non-constant value
 
 error: aborting due to 4 previous errors
 
-For more information about this error, try `rustc --explain E0434`.
+For more information about this error, try `rustc --explain E0435`.
diff --git a/src/test/ui/issues/issue-27433.rs b/src/test/ui/issues/issue-27433.rs
index 2cc7d05e7c6..156ae68efe2 100644
--- a/src/test/ui/issues/issue-27433.rs
+++ b/src/test/ui/issues/issue-27433.rs
@@ -1,5 +1,5 @@
 fn main() {
     let foo = 42u32;
     const FOO : u32 = foo;
-                   //~^ ERROR can't capture dynamic environment
+                   //~^ ERROR attempt to use a non-constant value in a constant
 }
diff --git a/src/test/ui/issues/issue-27433.stderr b/src/test/ui/issues/issue-27433.stderr
index 78a193dd99a..e232d17e6d7 100644
--- a/src/test/ui/issues/issue-27433.stderr
+++ b/src/test/ui/issues/issue-27433.stderr
@@ -1,11 +1,9 @@
-error[E0434]: can't capture dynamic environment in a fn item
+error[E0435]: attempt to use a non-constant value in a constant
   --> $DIR/issue-27433.rs:3:23
    |
 LL |     const FOO : u32 = foo;
-   |                       ^^^
-   |
-   = help: use the `|| { ... }` closure form instead
+   |                       ^^^ non-constant value
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0434`.
+For more information about this error, try `rustc --explain E0435`.
diff --git a/src/test/ui/issues/issue-3521-2.rs b/src/test/ui/issues/issue-3521-2.rs
index 39f7fcb8337..871394f9eae 100644
--- a/src/test/ui/issues/issue-3521-2.rs
+++ b/src/test/ui/issues/issue-3521-2.rs
@@ -2,7 +2,7 @@ fn main() {
     let foo = 100;
 
     static y: isize = foo + 1;
-    //~^ ERROR can't capture dynamic environment
+    //~^ ERROR attempt to use a non-constant value in a constant
 
     println!("{}", y);
 }
diff --git a/src/test/ui/issues/issue-3521-2.stderr b/src/test/ui/issues/issue-3521-2.stderr
index 1464fd74bba..d54bbbcdc33 100644
--- a/src/test/ui/issues/issue-3521-2.stderr
+++ b/src/test/ui/issues/issue-3521-2.stderr
@@ -1,11 +1,9 @@
-error[E0434]: can't capture dynamic environment in a fn item
+error[E0435]: attempt to use a non-constant value in a constant
   --> $DIR/issue-3521-2.rs:4:23
    |
 LL |     static y: isize = foo + 1;
-   |                       ^^^
-   |
-   = help: use the `|| { ... }` closure form instead
+   |                       ^^^ non-constant value
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0434`.
+For more information about this error, try `rustc --explain E0435`.
diff --git a/src/test/ui/issues/issue-3668-2.rs b/src/test/ui/issues/issue-3668-2.rs
index 265a884ded7..525f6f5684e 100644
--- a/src/test/ui/issues/issue-3668-2.rs
+++ b/src/test/ui/issues/issue-3668-2.rs
@@ -1,6 +1,6 @@
 fn f(x:isize) {
     static child: isize = x + 1;
-    //~^ ERROR can't capture dynamic environment
+    //~^ ERROR attempt to use a non-constant value in a constant
 }
 
 fn main() {}
diff --git a/src/test/ui/issues/issue-3668-2.stderr b/src/test/ui/issues/issue-3668-2.stderr
index 8dd6f49d8de..d6a6e837960 100644
--- a/src/test/ui/issues/issue-3668-2.stderr
+++ b/src/test/ui/issues/issue-3668-2.stderr
@@ -1,11 +1,9 @@
-error[E0434]: can't capture dynamic environment in a fn item
+error[E0435]: attempt to use a non-constant value in a constant
   --> $DIR/issue-3668-2.rs:2:27
    |
 LL |     static child: isize = x + 1;
-   |                           ^
-   |
-   = help: use the `|| { ... }` closure form instead
+   |                           ^ non-constant value
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0434`.
+For more information about this error, try `rustc --explain E0435`.
diff --git a/src/test/ui/issues/issue-3668.rs b/src/test/ui/issues/issue-3668.rs
index 3f61b1b02e7..0e1f19a75ba 100644
--- a/src/test/ui/issues/issue-3668.rs
+++ b/src/test/ui/issues/issue-3668.rs
@@ -6,7 +6,7 @@ trait PTrait {
 impl PTrait for P {
    fn getChildOption(&self) -> Option<Box<P>> {
        static childVal: Box<P> = self.child.get();
-       //~^ ERROR can't capture dynamic environment
+       //~^ ERROR attempt to use a non-constant value in a constant
        panic!();
    }
 }
diff --git a/src/test/ui/issues/issue-3668.stderr b/src/test/ui/issues/issue-3668.stderr
index 7f974de9da8..98cd3631a53 100644
--- a/src/test/ui/issues/issue-3668.stderr
+++ b/src/test/ui/issues/issue-3668.stderr
@@ -1,11 +1,9 @@
-error[E0434]: can't capture dynamic environment in a fn item
+error[E0435]: attempt to use a non-constant value in a constant
   --> $DIR/issue-3668.rs:8:34
    |
 LL |        static childVal: Box<P> = self.child.get();
-   |                                  ^^^^
-   |
-   = help: use the `|| { ... }` closure form instead
+   |                                  ^^^^ non-constant value
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0434`.
+For more information about this error, try `rustc --explain E0435`.
diff --git a/src/test/ui/type/type-dependent-def-issue-49241.rs b/src/test/ui/type/type-dependent-def-issue-49241.rs
index 4c366a86363..51bd116fbd6 100644
--- a/src/test/ui/type/type-dependent-def-issue-49241.rs
+++ b/src/test/ui/type/type-dependent-def-issue-49241.rs
@@ -1,6 +1,6 @@
 fn main() {
     let v = vec![0];
-    const l: usize = v.count(); //~ ERROR can't capture dynamic environment in a fn item
+    const l: usize = v.count(); //~ ERROR attempt to use a non-constant value in a constant
     let s: [u32; l] = v.into_iter().collect();
     //~^ ERROR evaluation of constant value failed
 }
diff --git a/src/test/ui/type/type-dependent-def-issue-49241.stderr b/src/test/ui/type/type-dependent-def-issue-49241.stderr
index 8783959f45f..0af777fdcf9 100644
--- a/src/test/ui/type/type-dependent-def-issue-49241.stderr
+++ b/src/test/ui/type/type-dependent-def-issue-49241.stderr
@@ -1,10 +1,8 @@
-error[E0434]: can't capture dynamic environment in a fn item
+error[E0435]: attempt to use a non-constant value in a constant
   --> $DIR/type-dependent-def-issue-49241.rs:3:22
    |
-LL |     const l: usize = v.count(); //~ ERROR can't capture dynamic environment in a fn item
-   |                      ^
-   |
-   = help: use the `|| { ... }` closure form instead
+LL |     const l: usize = v.count(); //~ ERROR attempt to use a non-constant value in a constant
+   |                      ^ non-constant value
 
 error[E0080]: evaluation of constant value failed
   --> $DIR/type-dependent-def-issue-49241.rs:4:18
@@ -14,5 +12,5 @@ LL |     let s: [u32; l] = v.into_iter().collect();
 
 error: aborting due to 2 previous errors
 
-Some errors occurred: E0080, E0434.
+Some errors occurred: E0080, E0435.
 For more information about an error, try `rustc --explain E0080`.