diff --git a/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl b/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl
index 4d4954d811..31c3883cbf 100644
--- a/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl
+++ b/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl
@@ -3711,6 +3711,16 @@
 
 (test 'c dynamic-require ''check-jit-registers-shortcut 'result)
 
+;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;  Check (non-)inference of flonums with `if` branches:
+
+(let ()
+  (define f (lambda (x)
+              (let ([v (if x 1 2.0)])
+                (fl+ v v))))
+  (set! f f)
+  (err/rt-test (f #t)))
+
 ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (report-errs)
diff --git a/racket/src/racket/src/optimize.c b/racket/src/racket/src/optimize.c
index 53edbcaf83..d986b85a54 100644
--- a/racket/src/racket/src/optimize.c
+++ b/racket/src/racket/src/optimize.c
@@ -2021,8 +2021,14 @@ static int expr_produces_local_type(Scheme_Object *expr, int fuel)
     case scheme_branch_type:
       {
         Scheme_Branch_Rec *b = (Scheme_Branch_Rec *)expr;
-        return (expr_produces_local_type(b->tbranch, fuel / 2)
-                && expr_produces_local_type(b->fbranch, fuel / 2));
+        int t1, t2;
+
+        t1 = expr_produces_local_type(b->tbranch, fuel / 2);
+        if (t1) {
+          t2 = expr_produces_local_type(b->fbranch, fuel / 2);
+          return ((t1 == t2) ? t1 : 0);
+        } else
+          return 0;
       }
       break;
     case scheme_sequence_type: