diff --git a/src/BuiltinFn.zig b/src/BuiltinFn.zig
index 1715060afc7f6c0b6f99f0356e7384a9b16702a8..3964512838584859cff215fd77c87f6b7dfd8e1f 100644
--- a/src/BuiltinFn.zig
+++ b/src/BuiltinFn.zig
@@ -153,7 +153,7 @@ pub const list = list: {
             "@asyncCall",
             .{
                 .tag = .async_call,
-                .param_count = null,
+                .param_count = 4,
             },
         },
         .{