diff --git a/gen_commands.py b/gen_commands.py
index d7fb565bd4..b737cd67d5 100644
--- a/gen_commands.py
+++ b/gen_commands.py
@@ -112,7 +112,7 @@ constexpr auto MakeCallback() noexcept {
     }
 }
 
-template <Commands Tcmd, typename... Targs, typename T, T... i>
+template <Commands Tcmd, typename... Targs, size_t... i>
 inline constexpr auto MakeDispatchTableHelper(std::index_sequence<i...>) noexcept
 {
     return std::array<bool (*)(StringID err_msg, TileIndex tile, Targs...), sizeof...(i)>{MakeCallback<Tcmd, i, Targs...>()... };
diff --git a/src/citymania/generated/cm_gen_commands.cpp b/src/citymania/generated/cm_gen_commands.cpp
index 13f87d9ed5..916676c22f 100644
--- a/src/citymania/generated/cm_gen_commands.cpp
+++ b/src/citymania/generated/cm_gen_commands.cpp
@@ -93,7 +93,7 @@ constexpr auto MakeCallback() noexcept {
     }
 }
 
-template <Commands Tcmd, typename... Targs, typename T, T... i>
+template <Commands Tcmd, typename... Targs, size_t... i>
 inline constexpr auto MakeDispatchTableHelper(std::index_sequence<i...>) noexcept
 {
     return std::array<bool (*)(StringID err_msg, TileIndex tile, Targs...), sizeof...(i)>{MakeCallback<Tcmd, i, Targs...>()... };