diff --git a/newlib/libc/sys/rtems/include/machine/_arc4random.h b/newlib/libc/sys/rtems/include/machine/_arc4random.h
index 7ef296899..83b8493f1 100644
--- a/newlib/libc/sys/rtems/include/machine/_arc4random.h
+++ b/newlib/libc/sys/rtems/include/machine/_arc4random.h
@@ -28,7 +28,7 @@
 
 __BEGIN_DECLS
 
-void _arc4random_getentropy_fail(void);
+_Noreturn void _arc4random_getentropy_fail(void);
 
 #define _ARC4RANDOM_GETENTROPY_FAIL() _arc4random_getentropy_fail()