diff --git a/RedPandaIDE/problems/competitivecompenionhandler.h b/RedPandaIDE/problems/competitivecompenionhandler.h
index a12e6098..7a7bc875 100644
--- a/RedPandaIDE/problems/competitivecompenionhandler.h
+++ b/RedPandaIDE/problems/competitivecompenionhandler.h
@@ -21,7 +21,7 @@
 #include <QThread>
 #include <QSemaphore>
 
-class OJProblem;
+struct OJProblem;
 using POJProblem = std::shared_ptr<OJProblem>;
 
 class QTcpSocket;
diff --git a/RedPandaIDE/xmake.lua b/RedPandaIDE/xmake.lua
index f58e2e20..a3510fcc 100644
--- a/RedPandaIDE/xmake.lua
+++ b/RedPandaIDE/xmake.lua
@@ -88,6 +88,8 @@ target("RedPandaIDE")
         -- parser
         "parser/cppparser",
         "parser/statementmodel",
+        -- problems
+        "problems/competitivecompenionhandler",
         -- settings dialog
         "settingsdialog/settingswidget",
         -- widgets
diff --git a/libs/qsynedit/qsynedit/qsynedit.h b/libs/qsynedit/qsynedit/qsynedit.h
index 6c385526..f05daf14 100644
--- a/libs/qsynedit/qsynedit/qsynedit.h
+++ b/libs/qsynedit/qsynedit/qsynedit.h
@@ -138,7 +138,7 @@ class TokenAttribute;
 using PTokenAttribute = std::shared_ptr<TokenAttribute>;
 class Document;
 using PDocument = std::shared_ptr<Document>;
-class SyntaxState;
+struct SyntaxState;
 class Syntaxer;
 using PSyntaxer = std::shared_ptr<Syntaxer>;
 class UndoList;