2 files changed, 32 insertions, 0 deletions
diff --git a/test/mono/pass/union-exist2 b/test/mono/pass/union-exist2
new file mode 100644
index 00000000..9852a125
--- /dev/null
+++ b/test/mono/pass/union-exist2
@@ -0,0 +1 @@
+union-exist2.sail -auto_mono
diff --git a/test/mono/union-exist2.sail b/test/mono/union-exist2.sail
new file mode 100644
index 00000000..aede3c0d
--- /dev/null
+++ b/test/mono/union-exist2.sail
@@ -0,0 +1,31 @@
+default Order dec
+$include <prelude.sail>
+
+union myunion = {
+  MyConstr : {'n 'm 'o, 'n in {8,16} & 'o in {8,16} & 'n <= 'm & 'm <= 'o. (int('n),bits('n),int('o),bits('o),int('m))}
+}
+
+val make : bits(2) -> myunion
+
+function make(v) =
+  let (n,v,m) : {'n 'm, 'n in {8,16} & 'm in {8,16} & 'n <= 'm. (int('n),bits('n),int('m))} = match v {
+    0b00 => ( 8,  0x12, 8),
+    0b01 => (16,0x1234,16),
+    0b10 => ( 8,  0x56,16),
+    0b11 => (16,0x5678,16)
+  } in
+  let w = sail_zero_extend(0x5,m) in
+  MyConstr(n,v,m,w,m)
+
+val use : myunion -> bits(32)
+
+function use(MyConstr(n,v,_,_,_)) = sail_zero_extend(v,32)
+
+val run : unit -> unit effect {escape}
+
+function run () = {
+  assert(use(make(0b00)) == 0x00000012);
+  assert(use(make(0b01)) == 0x00001234);
+  assert(use(make(0b10)) == 0x00000056);
+  assert(use(make(0b11)) == 0x00005678);
+}