diff --git a/doc/docgen.zig b/doc/docgen.zig
index e2da1fe6cc797a0d6e9d57038e0f5ffbcd11f798..4d66b43efd27cfad666da9efdf052b1be2fa7a1f 100644
--- a/doc/docgen.zig
+++ b/doc/docgen.zig
@@ -370,9 +370,9 @@ fn genToc(allocator: *mem.Allocator, tokenizer: *Tokenizer) !Toc {
                             .n = header_stack_size,
                         },
                     });
-                    if (try urls.put(urlized, tag_token)) |other_tag_token| {
+                    if (try urls.put(urlized, tag_token)) |entry| {
                         parseError(tokenizer, tag_token, "duplicate header url: #{}", urlized) catch {};
-                        parseError(tokenizer, other_tag_token, "other tag here") catch {};
+                        parseError(tokenizer, entry.value, "other tag here") catch {};
                         return error.ParseError;
                     }
                     if (last_action == Action.Open) {