chore: add TODO comment

Author: robbielyman

build/luajit.zig

@@ -123,6 +123,7 @@ pub fn configure(b: *Build, target: Build.ResolvedTarget, optimize: std.builtin.
     const buildvm_os_c_flags: []const []const u8 = if (target.result.os.tag == .windows)
         &.{"-DLUAJIT_OS=1"}
     else if (target.result.os.tag.isDarwin())
+        // FIXME: this can be removed once https://codeberg.org/ziglang/zig/issues/30669 is successfully resolved
         &.{"-DLJ_NO_UNWIND=1"}
     else
         &.{};