diff --git a/include/ruby/3/core/rarray.h b/include/ruby/3/core/rarray.h
index f4f6809874..cd8767a8a8 100644
--- a/include/ruby/3/core/rarray.h
+++ b/include/ruby/3/core/rarray.h
@@ -123,7 +123,7 @@ RARRAY_EMBED_LEN(VALUE ary)
     VALUE f = RBASIC(ary)->flags;
     f &= RARRAY_EMBED_LEN_MASK;
     f >>= RARRAY_EMBED_LEN_SHIFT;
-    return (long)f;
+    return RUBY3_CAST((long)f);
 }
 
 RUBY3_ATTR_PURE_ON_NDEBUG()
diff --git a/include/ruby/3/core/rstring.h b/include/ruby/3/core/rstring.h
index 3d40f850bc..80e997b494 100644
--- a/include/ruby/3/core/rstring.h
+++ b/include/ruby/3/core/rstring.h
@@ -108,7 +108,7 @@ RSTRING_EMBED_LEN(VALUE str)
     VALUE f = RBASIC(str)->flags;
     f &= RSTRING_EMBED_LEN_MASK;
     f >>= RSTRING_EMBED_LEN_SHIFT;
-    return (long)f;
+    return RUBY3_CAST((long)f);
 }
 
 RUBY3_ATTR_PURE_ON_NDEBUG()