diff --git a/cfg/posix.cfg b/cfg/posix.cfg
index 1302533a2..6e313e584 100644
--- a/cfg/posix.cfg
+++ b/cfg/posix.cfg
@@ -1,5 +1,6 @@
 <?xml version="1.0"?>
 <def>
   <function name="usleep"> <noreturn>false</noreturn> <arg nr="1"><not-bool/><valid>0-999999</valid></arg> </function>
+  <function name="_exit"> <noreturn>true</noreturn> </function>
 </def>