Auto merge of #6945 - Manishearth:fixedme, r=jdm

If let is not an issue for lints

r? @Ms2ger

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1 files changed, 6 insertions, 4 deletions

diff --git a/components/plugins/lints/unrooted_must_root.rs b/components/plugins/lints/unrooted_must_root.rs
index f07ed506fbd..dc116f311eb 100644
--- a/components/plugins/lints/unrooted_must_root.rs
+++ b/components/plugins/lints/unrooted_must_root.rs
@@ -202,10 +202,12 @@ impl LintPass for UnrootedPass {
                 // We need not check arms individually since enum/struct fields are already
                 // linted in `check_struct_def` and `check_variant`
                 // (so there is no way of destructuring out a `#[must_root]` field)
-                ast::ExprMatch(ref e, _, _) |
-                // For loops allow you to bind a return value locally
-                ast::ExprForLoop(_, ref e, _, _) => &**e,
-                // XXXManishearth look into `if let` once it lands in our rustc
+                ast::ExprMatch(ref e, _, _) => &**e,
+                // These are able to bind local variables, but are desugared into
+                // loops and matches pre-lint so should not be encountered
+                ast::ExprForLoop(..) => unreachable!(),
+                ast::ExprIfLet(..) => unreachable!(),
+                ast::ExprWhileLet(..) => unreachable!(),
                 _ => return
             },
             _ => return