fix a syntax-object problem related to module bindings

The immediate symptom was that `(provide (all-defined-out))'
didn't work in a `module+'-based submodule, but there were
also non-submodule ways to expose the problem.

collects/tests/racket/module.rktl

@@ -659,6 +659,28 @@
   (require 'post-ex-rename-example-1)
   (go))
 
+;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; Check interaction of binding-context and mark:
+
+(module binding-context-a racket
+  (provide q)
+
+  (define-syntax (q stx)
+    (syntax-case stx ()
+      [(_ f) (with-syntax ([x (syntax-local-introduce #'x)])
+               #'(f x))])))
+
+(module binding-context-b racket
+  (require 'binding-context-a)
+
+  (define-syntax-rule (go id)
+    (begin
+      (define id 5)
+      (define-syntax-rule (prov)
+        (provide id))
+      (prov)))
+  
+  (q go))
 
 ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 

collects/tests/racket/submodule.rktl

@@ -447,6 +447,16 @@
 (test 'c (dynamic-require '(submod 'subm-example-20 third) 'third) '(a b c))
 (test 'c (dynamic-require '(submod 'subm-example-20 third) 't) '(a b c))
 
+;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; Check `all-defined-out':
+
+(module subm-all-defined-1 racket/base
+  (module+ main
+    (define x 10)
+    (provide (all-defined-out))))
+
+(test 10 dynamic-require '(submod 'subm-all-defined-1 main) 'x)
+
 ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (report-errs)

src/racket/src/compenv.c

@@ -1085,7 +1085,9 @@ Scheme_Object *scheme_tl_id_sym(Scheme_Env *env, Scheme_Object *id, Scheme_Objec
     marks = SCHEME_CAR(marks);
   }
 
-  if (!SCHEME_TRUEP(bdg))
+  /* Treat #f and void values of bdg the same, since a void value is
+     the same #f, but ensure that we get this far: */
+  if (SCHEME_FALSEP(bdg) || SCHEME_VOIDP(bdg))
     bdg = NULL;
 
   /* Find a mapping that matches the longest tail of marks */