diff --git a/pkgs/racket-pkgs/racket-test/tests/racket/number.rktl b/pkgs/racket-pkgs/racket-test/tests/racket/number.rktl
index 601d781166..408b19ef33 100644
--- a/pkgs/racket-pkgs/racket-test/tests/racket/number.rktl
+++ b/pkgs/racket-pkgs/racket-test/tests/racket/number.rktl
@@ -1243,6 +1243,31 @@
 (test 1 bitwise-bit-field (bitwise-not (expt 2 101)) 70 71)
 (test 7144187 bitwise-bit-field (expt 3 75) 0 24)
 
+;; More boundary checking, especially for returning a
+;; value that goes negative if mistreated as a fixnum:
+(let ()
+  (define (bitwise-bit-field* n start end)
+    (bitwise-and (sub1 (arithmetic-shift 1 (- end start)))
+                 (arithmetic-shift n (- start))))
+
+  (define (check-bit-field n)
+    (for ([i (in-range 200)])
+      (define lo 0)
+      (define hi i)
+      (test (bitwise-bit-field* n lo hi)
+            bitwise-bit-field n lo hi))
+    (for ([j (in-range 0 100)])
+      (for ([i (in-range j 200)])
+        (define lo (- i j))
+        (define hi i)
+        (test (bitwise-bit-field* n lo hi)
+              bitwise-bit-field n lo hi))))
+
+  (check-bit-field -1)
+  (check-bit-field (sub1 (expt 2 30)))
+  (check-bit-field (sub1 (expt 2 62)))
+  (check-bit-field (sub1 (arithmetic-shift 1 300))))
+
 (test 42 bitwise-bit-field 42 0 32)
 (test (sub1 (expt 2 32)) bitwise-bit-field -1 32 64)
 
diff --git a/racket/src/racket/src/number.c b/racket/src/racket/src/number.c
index cdeef1ead1..3c76539149 100644
--- a/racket/src/racket/src/number.c
+++ b/racket/src/racket/src/number.c
@@ -4276,9 +4276,9 @@ static Scheme_Object *bitwise_bit_field (int argc, Scheme_Object *argv[])
             if (v2 < (sizeof(intptr_t) * 8)) {
               if (SCHEME_INTP(so)) {
                 if (v1 < (sizeof(intptr_t) * 8)) {
-                  intptr_t res;
-                  res = ((SCHEME_INT_VAL(so) >> v1) & (((intptr_t)1 << v2) - 1));
-                  return scheme_make_integer(res);
+                  uintptr_t res;
+                  res = ((uintptr_t)(SCHEME_INT_VAL(so) >> v1) & (((uintptr_t)1 << v2) - 1));
+                  return scheme_make_integer_value_from_unsigned(res);
                 } else if (SCHEME_INT_VAL(so) > 0) 
                   return scheme_make_integer(0);
               } else if (SCHEME_BIGPOS(so)) {
@@ -4297,7 +4297,7 @@ static Scheme_Object *bitwise_bit_field (int argc, Scheme_Object *argv[])
                   d |= (((Scheme_Bignum *)so)->digits[vd + 1] << avail);
                 }
                 d = (d & (((bigdig)1 << v2) - 1));
-                return scheme_make_integer(d);
+                return scheme_make_integer_value_from_unsigned(d);
               }
             }
           }