A few improvements on pattern-matching compilation.

- Optimize the removal of generalization when there is no dependency in
  the generalized variable (see postprocess_dependencies, and the removal
  of dependencies in the default type of impossible cases).
- Compute the onlydflt flag correctly (what allows automatic treatment
  of impossible cases even when there is no clause at all).

1 files changed, 11 insertions, 0 deletions

diff --git a/test-suite/success/Case21.v b/test-suite/success/Case21.v
new file mode 100644
index 000000000..3f7877456
--- /dev/null
+++ b/test-suite/success/Case21.v
@@ -0,0 +1,11 @@
+(* Check insertion of impossible case when there is no branch at all *)
+
+Inductive eq_true : bool -> Prop :=  is_eq_true : eq_true true.
+
+Check fun H:eq_true false => match H with end : False.
+
+Inductive I : bool -> bool -> Prop := C : I true true.
+
+Check fun x (H:I x false) => match H with end : False.
+
+Check fun x (H:I false x) => match H with end : False.