X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=compiler%2Frustc_lint%2Fsrc%2Funused.rs;h=ecaf1c44354c5abf5c9d50084f83c2a5e61490d7;hb=a67649675014546ce454d65bc8fe3ebd18e6a319;hp=4c9b3df2dbd33d706d04c3cc5e911ceeb9c70a2c;hpb=9f82651a5fa4b1d96f55ce5507dd2aa204c7fb61;p=rust.git

diff --git a/compiler/rustc_lint/src/unused.rs b/compiler/rustc_lint/src/unused.rs
index 4c9b3df2dbd..ecaf1c44354 100644
--- a/compiler/rustc_lint/src/unused.rs
+++ b/compiler/rustc_lint/src/unused.rs
@@ -495,6 +495,7 @@ enum UnusedDelimsCtx {
     ArrayLenExpr,
     AnonConst,
     MatchArmExpr,
+    IndexExpr,
 }
 
 impl From<UnusedDelimsCtx> for &'static str {
@@ -514,6 +515,7 @@ fn from(ctx: UnusedDelimsCtx) -> &'static str {
             UnusedDelimsCtx::LetScrutineeExpr => "`let` scrutinee expression",
             UnusedDelimsCtx::ArrayLenExpr | UnusedDelimsCtx::AnonConst => "const expression",
             UnusedDelimsCtx::MatchArmExpr => "match arm expression",
+            UnusedDelimsCtx::IndexExpr => "index expression",
         }
     }
 }
@@ -661,6 +663,10 @@ fn emit_unused_delims(
         keep_space: (bool, bool),
     ) {
         let primary_span = if let Some((lo, hi)) = spans {
+            if hi.is_empty() {
+                // do not point at delims that do not exist
+                return;
+            }
             MultiSpan::from(vec![lo, hi])
         } else {
             MultiSpan::from(value_span)
@@ -733,6 +739,8 @@ fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &ast::Expr) {
                 (value, UnusedDelimsCtx::ReturnValue, false, Some(left), None)
             }
 
+            Index(_, ref value) => (value, UnusedDelimsCtx::IndexExpr, false, None, None),
+
             Assign(_, ref value, _) | AssignOp(.., ref value) => {
                 (value, UnusedDelimsCtx::AssignedValue, false, None, None)
             }