Convert untagged unions to tagged. Fix some edge cases in check-structures-sanity union checking.

library/include/df/custom/knowledge_scholar_category_flag.methods.inc

@@ -1,9 +1,9 @@
 df::enums::dfhack_knowledge_scholar_flag::dfhack_knowledge_scholar_flag value() const
 {
-    int32_t value = category * 32;
+    int32_t value = int32_t(flag_type) * 32;
     for (int32_t i = 0; i < 32; i++)
     {
-        if (flags.whole & (1 << i))
+        if (flag_data.whole & (1 << i))
         {
             value += i;
             break;

library/xml

@@ -1 +1 @@
-Subproject commit 17b1c45fff78d0c49aa8b4dc4824dc36ae7eae08
+Subproject commit caf5b7dfd090c73a0cb08b5507b588ea8f12bab9

plugins/devel/check-structures-sanity.cpp

@@ -6,6 +6,8 @@
 #include "LuaTools.h"
 #include "LuaWrapper.h"
 
+#include "df/large_integer.h"
+
 #if defined(WIN32) && defined(DFHACK64)
 #define _WIN32_WINNT 0x0501
 #define WINVER 0x0501
@@ -92,7 +94,7 @@ static const struct_field_info *find_union_tag(const struct_field_info *fields,
         name.erase(name.length() - 4, 4);
         name += "type";
 
-        if (tag_field->name == name)
+        if (tag_field->mode != struct_field_info::END && tag_field->name == name)
         {
             // fast path; we already have the correct field
         }
@@ -700,6 +702,13 @@ void Checker::check_dispatch(ToCheck & item)
         return;
     }
 
+    // special case for large_integer weirdness
+    if (item.identity == df::identity_traits<df::large_integer>::get())
+    {
+        item.identity = df::identity_traits<int64_t>::get();
+    }
+
+
     switch (item.identity->type())
     {
         case IDTYPE_GLOBAL: