flambda-backend: Fix freshening substitutions

Author: lpw25

boot/ocamlc

@@ -12,16 +12,16 @@ match (3, 2, 1) with
 ;;
 [%%expect{|
 (let
-  (*match*/88 = 3
-   *match*/89 = 2
-   *match*/90 = 1
-   *match*/91 = *match*/88
-   *match*/92 = *match*/89
-   *match*/93 = *match*/90)
+  (*match*/268 = 3
+   *match*/269 = 2
+   *match*/270 = 1
+   *match*/271 = *match*/268
+   *match*/272 = *match*/269
+   *match*/273 = *match*/270)
   (catch
     (catch
-      (catch (if (!= *match*/92 3) (exit 3) (exit 1)) with (3)
-        (if (!= *match*/91 1) (exit 2) (exit 1)))
+      (catch (if (!= *match*/272 3) (exit 3) (exit 1)) with (3)
+        (if (!= *match*/271 1) (exit 2) (exit 1)))
      with (2) 0)
    with (1) 1))
 - : bool = false
@@ -36,24 +36,25 @@ match (3, 2, 1) with
 ;;
 [%%expect{|
 (let
-  (*match*/96 = 3
-   *match*/97 = 2
-   *match*/98 = 1
-   *match*/99 = (makeblock 0 *match*/96 *match*/97 *match*/98))
+  (*match*/276 = 3
+   *match*/277 = 2
+   *match*/278 = 1
+   *match*/279 = (makeblock 0 *match*/276 *match*/277 *match*/278))
   (catch
     (catch
-      (let (*match*/100 =a (field 0 *match*/99))
+      (let (*match*/280 =a (field 0 *match*/279))
         (catch
-          (let (*match*/101 =a (field 1 *match*/99))
-            (if (!= *match*/101 3) (exit 7)
-              (let (*match*/102 =a (field 2 *match*/99)) (exit 5 *match*/99))))
+          (let (*match*/281 =a (field 1 *match*/279))
+            (if (!= *match*/281 3) (exit 7)
+              (let (*match*/282 =a (field 2 *match*/279))
+                (exit 5 *match*/279))))
          with (7)
-          (if (!= *match*/100 1) (exit 6)
+          (if (!= *match*/280 1) (exit 6)
             (let
-              (*match*/104 =a (field 2 *match*/99)
-               *match*/103 =a (field 1 *match*/99))
-              (exit 5 *match*/99)))))
+              (*match*/284 =a (field 2 *match*/279)
+               *match*/283 =a (field 1 *match*/279))
+              (exit 5 *match*/279)))))
      with (6) 0)
-   with (5 x/94[0: [int], [int], [int]]) (seq (ignore x/94) 1)))
+   with (5 x/274[0: [int], [int], [int]]) (seq (ignore x/274) 1)))
 - : bool = false
 |}];;

boot/ocamllex

@@ -103,9 +103,9 @@ include struct open struct type t = T end let x = T end
 Line 1, characters 15-41:
 1 | include struct open struct type t = T end let x = T end
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^
-Error: The type t/150 introduced by this open appears in the signature
+Error: The type t/330 introduced by this open appears in the signature
        Line 1, characters 46-47:
-         The value x has no valid type if t/150 is hidden
+         The value x has no valid type if t/330 is hidden
 |}];;
 
 module A = struct
@@ -123,9 +123,9 @@ Lines 3-6, characters 4-7:
 4 |       type t = T
 5 |       let x = T
 6 |     end
-Error: The type t/155 introduced by this open appears in the signature
+Error: The type t/335 introduced by this open appears in the signature
        Line 7, characters 8-9:
-         The value y has no valid type if t/155 is hidden
+         The value y has no valid type if t/335 is hidden
 |}];;
 
 module A = struct
@@ -142,9 +142,9 @@ Lines 3-5, characters 4-7:
 3 | ....open struct
 4 |       type t = T
 5 |     end
-Error: The type t/160 introduced by this open appears in the signature
+Error: The type t/340 introduced by this open appears in the signature
        Line 6, characters 8-9:
-         The value y has no valid type if t/160 is hidden
+         The value y has no valid type if t/340 is hidden
 |}]
 
 (* It was decided to not allow this anymore. *)

testsuite/tests/basic/patmatch_for_multiple.ml

@@ -362,7 +362,7 @@ val foo : int foo -> int = <fun>
 Line 3, characters 26-31:
 3 |   | { x = (x : int); eq = Refl3 } -> x
                               ^^^^^
-Warning 18 [not-principal]: typing this pattern requires considering M.t and int as equal.
+Warning 18 [not-principal]: typing this pattern requires considering M.t and N.t as equal.
 But the knowledge of these types is not principal.
 val foo : int foo -> int = <fun>
 |}]

testsuite/tests/generalized-open/gpr1506.ml

@@ -24,11 +24,11 @@ end
 Line 3, characters 2-36:
 3 |   include Comparable with type t = t
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Error: Illegal shadowing of included type t/98 by t/102
+Error: Illegal shadowing of included type t/278 by t/282
        Line 2, characters 2-19:
-         Type t/98 came from this include
+         Type t/278 came from this include
        Line 3, characters 2-23:
-         The value print has no valid type if t/98 is shadowed
+         The value print has no valid type if t/278 is shadowed
 |}]
 
 module type Sunderscore = sig