fix module->namespace problem resoring bindings

If a module has any sort of complex bindings, such as a definition of
a macor-introduced identifiers, then `module->namespace` and variants
(like `variable-reference->namespace`) need to recreate suitable
bindings. Make sure that the module-path index for recreated bindings
is the run-time one, not the compile-time one.

Closes #1584

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

@@ -2017,6 +2017,37 @@ case of module-leve bindings; it doesn't cover local bindings.
   (parameterize ([read-accept-compiled #t])
     (read (open-input-bytes (get-output-bytes o)))))
 
+;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; Make sure that when `variable-reference->namespace`
+;; reconstitutes variable mappings, that it uses the
+;; run-time module path index of the module instead
+;; of it's compile-time module path index
+
+(parameterize ([current-module-declare-name
+                (make-resolved-module-path 'uses-own-namespace-for-eval-from-submodule)])
+  (eval
+   '(module m racket/base
+     (require (for-syntax racket/base))
+
+     (define (x) 1)
+
+     (define-syntax-rule (def) (define y 0))
+     (def)
+
+     (void
+      (variable-reference->namespace (#%variable-reference)))
+
+     (define (get-x)
+       (eval '(x) (variable-reference->namespace (#%variable-reference))))
+
+     (module* main #f
+       (provide v)
+       (define v
+         (parameterize ([current-namespace (variable-reference->namespace (#%variable-reference))])
+           (eval '(get-x))))))))
+
+(test 1 dynamic-require '(submod 'uses-own-namespace-for-eval-from-submodule main) 'v)
+
 ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 (report-errs)

racket/src/racket/src/env.c

@@ -1613,7 +1613,9 @@ void scheme_shadow(Scheme_Env *env, Scheme_Object *n, Scheme_Object *val, int as
 
   scheme_add_module_binding(id, scheme_env_phase(env),
                             (env->module
-                             ? env->module->self_modidx
+                             ? (env->link_midx
+                                ? env->link_midx
+                                : env->module->self_modidx)
                              : scheme_false),
                             ((env->module && env->module->prefix)
                              ? env->module->prefix->src_insp_desc