Add FAQ for NLL migration

[rust.git] / src / test / ui / empty / empty-never-array.stderr

diff --git a/src/test/ui/empty/empty-never-array.stderr b/src/test/ui/empty/empty-never-array.stderr
index e409f14d6ce97272fdc1512afec1029012a36c8c..9911dd4683b6664a69b47d9e7b3a85fb6eb96194 100644 (file)
--- a/src/test/ui/empty/empty-never-array.stderr
+++ b/src/test/ui/empty/empty-never-array.stderr
@@ -1,9 +1,27 @@
 error[E0005]: refutable pattern in local binding: `T(_, _)` not covered
   --> $DIR/empty-never-array.rs:10:9
    |
-LL |     let Helper::U(u) = Helper::T(t, []);
-   |         ^^^^^^^^^^^^ pattern `T(_, _)` not covered
+LL | / enum Helper<T, U> {
+LL | |     T(T, [!; 0]),
+LL | |     #[allow(dead_code)]
+LL | |     U(U),
+LL | | }
+   | |_- `Helper<T, U>` defined here
+...
+LL |       let Helper::U(u) = Helper::T(t, []);
+   |           ^^^^^^^^^^^^ pattern `T(_, _)` not covered
+
+warning[E0381]: use of possibly uninitialized variable: `u`
+  --> $DIR/empty-never-array.rs:12:5
+   |
+LL |     u
+   |     ^ use of possibly uninitialized `u`
+   |
+   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
+   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
+   = note: for more information, try `rustc --explain E0729`
 
 error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0005`.
+Some errors have detailed explanations: E0005, E0381.
+For more information about an error, try `rustc --explain E0005`.