expander: fix tracking of submodule base scopes

When expanding a `(module* _name #f ...)` submodule, accumulate all
module scopes on the `#f` and use the `#f` for a reexpansion.
Attempting to start each time from the enclosing module's scope loses
scopes that were generated from previous expansions. One consequence
of losind a scope is that an original definition may appear to be
macro-introduced, and the defined variable may become inaccessible
in the module's namespace.

pkgs/racket-test-core/tests/racket/module.rktl

@@ -2721,6 +2721,21 @@ case of module-leve bindings; it doesn't cover local bindings.
                   (list #'module* #'stop)
                   #:extend-stop-ids? #f)))
 
+;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; Make sure that re-expansion of a `(module _name #f ....)`
+;; submodule doesn't lose track of the base scope of the
+;; submodule --- which would, for example, cause a definition
+;; of `x` in the original submodule to be mapped to an
+;; inaccessible `x.1`.
+
+(parameterize ([current-namespace (make-base-namespace)])
+  (eval-syntax (expand '(module m racket/base
+                          (require syntax/location)
+                          (module* check #f
+                            (define x 42)))))
+  (dynamic-require '(submod 'm check) #f)
+  (eval 'x (module->namespace '(submod 'm check))))
+
 ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (report-errs)

racket/src/expander/expand/module.rkt

@@ -85,7 +85,6 @@
 (define (expand-module s init-ctx enclosing-self
                        #:always-produce-compiled? [always-produce-compiled? #f]
                        #:keep-enclosing-scope-at-phase [keep-enclosing-scope-at-phase #f]
-                       #:enclosing-all-scopes-stx [enclosing-all-scopes-stx #f]
                        #:enclosing-is-cross-phase-persistent? [enclosing-is-cross-phase-persistent? #f]
                        #:enclosing-requires+provides [enclosing-r+p #f]
                        #:mpis-for-enclosing-reset [mpis-for-enclosing-reset #f]
@@ -129,11 +128,7 @@
 
    ;; Initial require name provides the module's base scopes
    (define initial-require-s (apply-module-scopes (m 'initial-require)))
-   (define all-scopes-s (if enclosing-all-scopes-stx
+   (define all-scopes-s initial-require-s)
-                            (apply-module-scopes
-                             (syntax-shift-phase-level enclosing-all-scopes-stx
-                                                       keep-enclosing-scope-at-phase))
-                            initial-require-s))
 
    (define root-ctx (make-root-expand-context
                      #:self-mpi self
@@ -1240,7 +1235,6 @@
                  (expand-submodule shifted-s self submod-ctx
                                    #:is-star? #t
                                    #:keep-enclosing-scope-at-phase neg-phase
-                                   #:enclosing-all-scopes-stx all-scopes-s
                                    #:enclosing-requires+provides requires+provides
                                    #:enclosing-is-cross-phase-persistent? enclosing-is-cross-phase-persistent?
                                    #:mpis-to-reset mpis-to-reset
@@ -1321,7 +1315,6 @@
                           #:keep-enclosing-scope-at-phase [keep-enclosing-scope-at-phase #f]
                           #:enclosing-requires+provides [enclosing-r+p #f]
                           #:enclosing-is-cross-phase-persistent? [enclosing-is-cross-phase-persistent? #f]
-                          #:enclosing-all-scopes-stx [enclosing-all-scopes-stx #f]
                           #:mpis-to-reset mpis-to-reset
                           #:declared-submodule-names declared-submodule-names
                           #:compiled-submodules compiled-submodules
@@ -1347,7 +1340,6 @@
                    self
                    #:always-produce-compiled? #t
                    #:keep-enclosing-scope-at-phase keep-enclosing-scope-at-phase
-                   #:enclosing-all-scopes-stx enclosing-all-scopes-stx
                    #:enclosing-requires+provides enclosing-r+p
                    #:enclosing-is-cross-phase-persistent? enclosing-is-cross-phase-persistent?
                    #:mpis-for-enclosing-reset mpis-to-reset