diff --git a/src/test/scala/leon/test/verification/XLangVerificationRegression.scala b/src/test/scala/leon/test/verification/XLangVerificationRegression.scala
index 9509e08989759c6eb29e49410842be3bce1a3333..a22df5438706b39343929af3ad7cab344547bca9 100644
--- a/src/test/scala/leon/test/verification/XLangVerificationRegression.scala
+++ b/src/test/scala/leon/test/verification/XLangVerificationRegression.scala
@@ -26,7 +26,7 @@ class XLangVerificationRegression extends FunSuite {
     xlang.FunctionClosure andThen
     leon.verification.AnalysisPhase
 
-  private def mkTest(file : File)(block: Output=>Unit) = {
+  private def mkTest(file : File, forError: Boolean = false)(block: Output=>Unit) = {
     val fullName = file.getPath()
     val start = fullName.indexOf("regression")
 
@@ -55,22 +55,32 @@ class XLangVerificationRegression extends FunSuite {
 
       val pipeline = mkPipeline
 
-      val report = pipeline.run(ctx)(file.getPath :: Nil)
+      if(forError) {
+        intercept[LeonFatalError]{
+          pipeline.run(ctx)(file.getPath :: Nil)
+        }
+      } else {
+
+        val report = pipeline.run(ctx)(file.getPath :: Nil)
+
+        block(Output(report, ctx.reporter))
+      }
 
-      block(Output(report, ctx.reporter))
     }
   }
 
-  private def forEachFileIn(cat : String)(block : Output=>Unit) {
+  private def forEachFileIn(cat : String, forError: Boolean = false)(block : Output=>Unit) {
     val fs = filesInResourceDir(
       "regression/verification/xlang/" + cat,
       _.endsWith(".scala"))
 
     for(f <- fs) {
-      mkTest(f)(block)
+      mkTest(f, forError)(block)
     }
   }
   
+  forEachFileIn("error", true) { output => () }
+
   forEachFileIn("valid") { output =>
     val Output(report, reporter) = output
     assert(report.totalConditions === report.totalValid,