diff --git a/regression/cbmc-concurrency/stack1/test.desc b/regression/cbmc-concurrency/stack1/test.desc
index 52168c7eba4..8ecf05b6d5c 100644
--- a/regression/cbmc-concurrency/stack1/test.desc
+++ b/regression/cbmc-concurrency/stack1/test.desc
@@ -1,4 +1,4 @@
-KNOWNBUG
+CORE pthread
 main.c
 
 ^EXIT=0$