Fix make-predicate at the top-level

This solves the immediate problem, but more generally the
handling of ignored syntax at the top-level seems very fishy.
There is a complicated protocol involving the top-level
type-checker returning #<void> for cases with no obvious
return type, but it's unclear if it actually works. That
code in tc-toplevel.rkt should be revamped in the future.

Closes PR 14030

Please merge into 6.0
(cherry picked from commit f292a9c0f2)

pkgs/typed-racket-pkgs/typed-racket-lib/typed-racket/base-env/prims.rkt

@@ -262,17 +262,18 @@ This file defines two sorts of primitives. All of them are provided into any mod
          (if (Error? typ)
              ;; This code should never get run, typechecking will have an error earlier
              #`(error 'make-predicate "Couldn't parse type")
-             #`(ann
+             #`(let ()
-               #,(ignore-some-property
+                 (ann
-                   (type->contract
+                  #,(ignore-some-property
-                     typ
+                     (type->contract
-                     ;; must be a flat contract
+                      typ
-                     #:kind 'flat
+                      ;; must be a flat contract
-                     ;; the value is not from the typed side
+                      #:kind 'flat
-                     #:typed-side #f
+                      ;; the value is not from the typed side
-                     (type->contract-fail typ #'ty #:ctc-str "predicate"))
+                      #:typed-side #f
-                   #t)
+                      (type->contract-fail typ #'ty #:ctc-str "predicate"))
-               (Any -> Boolean : ty)))))]))
+                     #t)
+                  (Any -> Boolean : ty))))))]))
 
 (define-syntax (cast stx)
   (syntax-parse stx

pkgs/typed-racket-pkgs/typed-racket-test/tests/typed-racket/succeed/top-level-make-predicate.rkt

@@ -0,0 +1,5 @@
+#lang racket/load
+;; Test for PR 14030
+(require typed/racket)
+(make-predicate Integer)
+