diff --git a/libs/main/core/pistring.h b/libs/main/core/pistring.h
index 800e9df7..98557968 100644
--- a/libs/main/core/pistring.h
+++ b/libs/main/core/pistring.h
@@ -77,6 +77,16 @@ public:
 	PIString & operator +=(const PIString & str);
 	PIString & operator +=(const PIConstChars & str);
 
+	PIString(uchar ) = delete;
+	PIString( short) = delete;
+	PIString(ushort) = delete;
+	PIString( int  ) = delete;
+	PIString(uint  ) = delete;
+	PIString( long ) = delete;
+	PIString(ulong ) = delete;
+	PIString( llong) = delete;
+	PIString(ullong) = delete;
+
 	PIString & operator +=(uchar ) = delete;
 	PIString & operator +=( short) = delete;
 	PIString & operator +=(ushort) = delete;