Fix #6323: stronger restrict universe context vs abstract.

In the test we do [let X : Type@{i} := Set in ...] with Set
abstracted. The constraint [Set < i] was lost in the abstract.

Universes of a monomorphic reference [c] are considered to appear in
the term [c].

1 files changed, 9 insertions, 0 deletions

diff --git a/test-suite/bugs/closed/6323.v b/test-suite/bugs/closed/6323.v
new file mode 100644
index 000000000..fdc33befc
--- /dev/null
+++ b/test-suite/bugs/closed/6323.v
@@ -0,0 +1,9 @@
+Goal True.
+  simple refine (let X : Type := _ in _);
+    [ abstract exact Set using Set'
+    | let X' := (eval cbv delta [X] in X) in
+      clear X;
+      simple refine (let id' : { x : X' | True } -> X' := _ in _);
+      [ abstract refine (@proj1_sig _ _) | ]
+    ].
+Abort.