diff --git a/src/plugins/e-acsl/interval.ml b/src/plugins/e-acsl/interval.ml
index 3fcdc8e37c7a50e030b5a3b6f717d3e343811cc1..bdb28cf0ffa60fe5311f34eb895e8aa50aa0f7fd 100644
--- a/src/plugins/e-acsl/interval.ml
+++ b/src/plugins/e-acsl/interval.ml
@@ -117,7 +117,8 @@ let lift_unop f = function
     (* any unary operator over a float generates a rational
        TODO: actually, certainly possible to generate a float *)
     Rational
-  | Rational | Real | Nan as i -> i
+  | Rational | Real | Nan as i ->
+    i
 
 let lift_binop ~safe_float f i1 i2 = match i1, i2 with
   | Ival iv, i when Ival.is_bottom iv -> i