Correct some spelling errors

Lintian found some spelling errors in the Debian packaging for coq. Fix
them most places they appear in the current source. (Don't change
documentation anchor names, as that would invalidate external
deeplinks.)

This also fixes a bug in coqdoc: prior to this commit, coqdoc would
highlight `instanciate` but not `instantiate`.

2 files changed, 3 insertions, 3 deletions

diff --git a/plugins/omega/PreOmega.v b/plugins/omega/PreOmega.v
index 094adfda7a..94a3d40441 100644
--- a/plugins/omega/PreOmega.v
+++ b/plugins/omega/PreOmega.v
@@ -183,7 +183,7 @@ Ltac zify_nat_op :=
         let t := eval compute in (Z.of_nat (S a)) in
         change (Z.of_nat (S a)) with t in H
       | _ => rewrite (Nat2Z.inj_succ a) in H
-      | _ => (* if the [rewrite] fails (most likely a dependent occurence of [Z.of_nat (S a)]),
+      | _ => (* if the [rewrite] fails (most likely a dependent occurrence of [Z.of_nat (S a)]),
                 hide [Z.of_nat (S a)] in this one hypothesis *)
         change (Z.of_nat (S a)) with (Z_of_nat' (S a)) in H
      end
@@ -194,7 +194,7 @@ Ltac zify_nat_op :=
         let t := eval compute in (Z.of_nat (S a)) in
         change (Z.of_nat (S a)) with t
       | _ => rewrite (Nat2Z.inj_succ a)
-      | _ => (* if the [rewrite] fails (most likely a dependent occurence of [Z.of_nat (S a)]),
+      | _ => (* if the [rewrite] fails (most likely a dependent occurrence of [Z.of_nat (S a)]),
                 hide [Z.of_nat (S a)] in the goal *)
         change (Z.of_nat (S a)) with (Z_of_nat' (S a))
      end
diff --git a/plugins/omega/omega.ml b/plugins/omega/omega.ml
index 2510c16934..7bca7c7099 100644
--- a/plugins/omega/omega.ml
+++ b/plugins/omega/omega.ml
@@ -178,7 +178,7 @@ let rec display_action print_var = function
       | DIVIDE_AND_APPROX (e1,e2,k,d) ->
           Printf.printf
             "Inequation E%d is divided by %s and the constant coefficient is \
-            rounded by substracting %s.\n" e1.id (sbi k) (sbi d)
+            rounded by subtracting %s.\n" e1.id (sbi k) (sbi d)
       | NOT_EXACT_DIVIDE (e,k) ->
           Printf.printf
             "Constant in equation E%d is not divisible by the pgcd \