diff options
| -rw-r--r-- | src/librustc_borrowck/borrowck/mod.rs | 6 | ||||
| -rw-r--r-- | src/test/compile-fail/issue-33819.rs | 9 | ||||
| -rw-r--r-- | src/test/ui/mismatched_types/main.stderr | 2 |
3 files changed, 16 insertions, 1 deletions
diff --git a/src/librustc_borrowck/borrowck/mod.rs b/src/librustc_borrowck/borrowck/mod.rs index 36222e172b8..819717628d6 100644 --- a/src/librustc_borrowck/borrowck/mod.rs +++ b/src/librustc_borrowck/borrowck/mod.rs @@ -977,7 +977,11 @@ impl<'a, 'tcx> BorrowckCtxt<'a, 'tcx> { if let Categorization::Local(local_id) = err.cmt.cat { let span = self.tcx.map.span(local_id); if let Ok(snippet) = self.tcx.sess.codemap().span_to_snippet(span) { - if snippet != "self" { + if snippet.starts_with("ref ") { + db.span_label(span, + &format!("use `{}` here to make mutable", + snippet.replace("ref ", "ref mut "))); + } else if snippet != "self" { db.span_label(span, &format!("use `mut {}` here to make mutable", snippet)); } diff --git a/src/test/compile-fail/issue-33819.rs b/src/test/compile-fail/issue-33819.rs new file mode 100644 index 00000000000..418e66dbd4d --- /dev/null +++ b/src/test/compile-fail/issue-33819.rs @@ -0,0 +1,9 @@ +fn main() { + let mut op = Some(2); + match op { + Some(ref v) => { let a = &mut v; }, + //~^ ERROR:cannot borrow immutable + //~| use `ref mut v` here to make mutable + None => {}, + } +} diff --git a/src/test/ui/mismatched_types/main.stderr b/src/test/ui/mismatched_types/main.stderr index 98bc11752e0..0e68c0d0b13 100644 --- a/src/test/ui/mismatched_types/main.stderr +++ b/src/test/ui/mismatched_types/main.stderr @@ -1,8 +1,10 @@ error: mismatched types [--explain E0308] --> $DIR/main.rs:14:18 + |> 14 |> let x: u32 = ( |> ^ expected u32, found () note: expected type `u32` note: found type `()` + error: aborting due to previous error |