Remove XML::Error.errors

spec/std/xml/reader_spec.cr

@@ -577,15 +577,5 @@ module XML
 
       reader.errors.map(&.to_s).should eq ["Opening and ending tag mismatch: people line 1 and foo"]
     end
-
-    it "adds errors to `XML::Error.errors` (deprecated)" do
-      XML::Error.errors # clear class error list
-
-      reader = XML::Reader.new(%(<people></foo>))
-      reader.read
-      reader.expand?
-
-      XML::Error.errors.try(&.map(&.to_s)).should eq ["Opening and ending tag mismatch: people line 1 and foo"]
-    end
   end
 end

src/xml/error.cr

@@ -11,22 +11,9 @@ class XML::Error < Exception
     super(message)
   end
 
-  @@errors = [] of self
-
-  # :nodoc:
-  protected def self.add_errors(errors)
-    @@errors.concat(errors)
-  end
-
   @[Deprecated("This class accessor is deprecated. XML errors are accessible directly in the respective context via `XML::Reader#errors` and `XML::Node#errors`.")]
   def self.errors : Array(XML::Error)?
-    if @@errors.empty?
-      nil
-    else
-      errors = @@errors.dup
-      @@errors.clear
-      errors
-    end
+    {% raise "`XML::Error.errors` was removed because it leaks memory when it's not used. XML errors are accessible directly in the respective context via `XML::Reader#errors` and `XML::Node#errors`.\nSee https://github.com/crystal-lang/crystal/issues/14934 for details. " %}
   end
 
   def self.collect(errors, &)

src/xml/reader.cr

@@ -198,9 +198,7 @@ class XML::Reader
   end
 
   private def collect_errors(&)
-    Error.collect(@errors) { yield }.tap do
-      Error.add_errors(@errors)
-    end
+    Error.collect(@errors) { yield }
   end
 
   private def check_no_null_byte(attribute)