diff --git a/test/Feature/undefined.ll b/test/Feature/undefined.ll
new file mode 100644
index 00000000000..a71b906dcc0
--- /dev/null
+++ b/test/Feature/undefined.ll
@@ -0,0 +1,15 @@
+
+%X = global int undef
+
+implementation
+
+declare int "atoi"(sbyte *)
+
+int %test() {
+	ret int undef
+}
+
+int %test2() {
+	%X = add int undef, 1
+	ret int %X
+}
diff --git a/test/Feature/unreachable.ll b/test/Feature/unreachable.ll
new file mode 100644
index 00000000000..84c4552a627
--- /dev/null
+++ b/test/Feature/unreachable.ll
@@ -0,0 +1,13 @@
+
+implementation
+
+declare void %bar()
+
+int %foo() {  ;; Calling this function has undefined behavior
+	unreachable
+}
+
+double %xyz() {
+	call void %bar()
+	unreachable          ;; Bar must not return.
+}