Fixes for MacOS 10.11 compatibility

modules/common/chowdsp_data_structures/Structures/chowdsp_OptionalRef.h

@@ -54,14 +54,14 @@ class OptionalRef
     T& value()
     {
         if (! has_value())
-            throw std::bad_optional_access();
+            throw std::runtime_error { "bad_optional_access" }; // we can't actually use std::bad_optional_access here for MacOS compatibility!
         return *ptr;
     }
 
     const T& value() const
     {
         if (! has_value())
-            throw std::bad_optional_access();
+            throw std::runtime_error { "bad_optional_access" };
         return *ptr;
     }
 

modules/common/chowdsp_data_structures/Structures/chowdsp_SmallVector.h

@@ -536,22 +536,22 @@
 
     auto& internal_array()
     {
-        return std::get<0> (internal_data);
+        return *std::get_if<0> (&internal_data);
     }
 
     const auto& internal_array() const
     {
-        return std::get<0> (internal_data);
+        return *std::get_if<0> (&internal_data);
     }
 
     auto& internal_vector()
     {
-        return std::get<1> (internal_data);
+        return *std::get_if<1> (&internal_data);
     }
 
     const auto& internal_vector() const
     {
-        return std::get<1> (internal_data);
+        return *std::get_if<1> (&internal_data);
     }
 
     struct ArrayStuff