MDEV-38410 segfault inside std::function

Segfault inside the standard library…
only memory corruption can explain it.

I have uncertain suspictions.

Author: ParadoxV5

sql/rpl_info_file.h

@@ -209,7 +209,7 @@ struct Info_file
   */
   struct Mem_fn: std::function<Persistent &(Info_file *self)>
   {
-    using List= const std::initializer_list<Mem_fn>;
+    using List= const std::initializer_list<const Mem_fn>;
     /// Null Constructor
     Mem_fn(std::nullptr_t null= nullptr):
       std::function<Persistent &(Info_file *)>(null) {}

sql/rpl_master_info_file.h

@@ -587,7 +587,8 @@ struct Master_info_file: Info_file
     keys should match the corresponding old property name in @ref Master_info.
   */
   // C++ default allocator to match that `mysql_execute_command()` uses `new`
-  inline static const std::unordered_map<std::string_view, Mem_fn> VALUE_MAP= {
+  inline static
+  const std::unordered_map<std::string_view, const Mem_fn> VALUE_MAP= {
     /*
       These are here to annotate whether they are `DEFAULT`.
       They are repeated from @ref VALUE_LIST to enable bidirectional