MSVC build: Silence 'C4100: unreferenced formal parameter' warnings

Added 'static_cast<void>(parameter-name)' in all paths where the parameter isn't used

4 files changed, 6 insertions, 0 deletions

diff --git a/sigc++/tuple-utils/tuple_end.h b/sigc++/tuple-utils/tuple_end.h
index 2f3572e..72526aa 100644
--- a/sigc++/tuple-utils/tuple_end.h
+++ b/sigc++/tuple-utils/tuple_end.h
@@ -56,6 +56,7 @@ tuple_end(T&& t) {
   static_assert(len <= size, "The tuple size must be less than or equal to the length.");
 
   if constexpr(len == 0) {
+    static_cast<void>(t);
     // Recursive calls to tuple_cdr() would result in this eventually,
     // but this avoids the extra work:
     return std::tuple<>();
diff --git a/sigc++/tuple-utils/tuple_for_each.h b/sigc++/tuple-utils/tuple_for_each.h
index e179ffe..8659d65 100644
--- a/sigc++/tuple-utils/tuple_for_each.h
+++ b/sigc++/tuple-utils/tuple_for_each.h
@@ -103,6 +103,8 @@ tuple_for_each(T&& t, T_extras&&... extras)
   {
     detail::tuple_for_each_impl<T_visitor, size, T_extras...>::tuple_for_each(
       std::forward<T>(t), std::forward<T_extras>(extras)...);
+  } else {
+    static_cast<void>(t);
   }
 }
 
diff --git a/sigc++/tuple-utils/tuple_transform_each.h b/sigc++/tuple-utils/tuple_transform_each.h
index 023cdbd..8d73764 100644
--- a/sigc++/tuple-utils/tuple_transform_each.h
+++ b/sigc++/tuple-utils/tuple_transform_each.h
@@ -35,6 +35,7 @@ struct tuple_transform_each_impl {
   static decltype(auto)
   tuple_transform_each(T_current&& t, T_original& t_original) {
     if constexpr(size_from_index == 0) {
+      static_cast<void>(t_original);
       //Do nothing because the tuple has no elements.
       return std::forward<T_current>(t);
     } else { //TODO: Should this compile without using else to contain the alternative code?
diff --git a/sigc++/visit_each.h b/sigc++/visit_each.h
index 46a0504..5f92120 100644
--- a/sigc++/visit_each.h
+++ b/sigc++/visit_each.h
@@ -47,6 +47,8 @@ struct limit_trackable_target
     //Only call action_() if T_Type derives from trackable.
     if constexpr(is_base_of_or_same_v<sigc::trackable, T_type>) {
         std::invoke(action_, type);
+    } else {
+      static_cast<void>(type);
     }
   }