diff --git a/src/test/scala/leon/regression/verification/XLangVerificationSuite.scala b/src/test/scala/leon/regression/verification/XLangVerificationSuite.scala
index 3a9783e7036ca82d51298b6eb1751e5ee024d46a..8511ebfea95d4d6a412d82922ffb1e6fb870d312 100644
--- a/src/test/scala/leon/regression/verification/XLangVerificationSuite.scala
+++ b/src/test/scala/leon/regression/verification/XLangVerificationSuite.scala
@@ -4,6 +4,8 @@ package leon.regression.verification
 
 import smtlib.interpreters.Z3Interpreter
 
+// If you add another regression test, make sure it contains exactly one object, whose name matches the file name.
+// This is because we compile all tests from each folder together.
 class XLangVerificationSuite extends VerificationSuite {
 
   val optionVariants: List[List[String]] = {