enter into the (guile) module when compiling boot-9.scm

* ice-9/boot-9.scm: Before doing very much, put us into the (guile)
  module when compiling. This avoids some circularity in the module boot
  process, whereby symbols are seen to resolve to the (guile-user)
  module, whereas in fact they originally pertain to the (guile) module.

ice-9/boot-9.scm

@@ -125,6 +125,14 @@
 
 
 
+;; Before compiling, make sure any symbols are resolved in the (guile)
+;; module, the primary location of those symbols, rather than in
+;; (guile-user), the default module that we compile in.
+
+(eval-case
+ ((compile-toplevel)
+  (set-current-module (resolve-module '(guile)))))
+
 ;;; {Defmacros}
 ;;;
 ;;; Depends on: features, eval-case