cmp: change handling of *cmp-env-root*

Due to the recent introduction of cross compilation features,
*cmp-env* has to contain type information throughout the entire
compilation (not only while we are compiling a form) so that (typep x
type *cmp-env*) works correctly. Therefore, we can't set *cmp-env* to
nil initially as we did previously. Instead, we set *cmp-env*
to *cmp-env-root* initially.

src/cmp/cmpglobals.lsp

@@ -231,7 +231,7 @@ be deleted if they have been opened with LoadLibrary.")
     (*callbacks* nil)
     (*functions* nil)
     (*cmp-env-root* (copy-tree *cmp-env-root*))
-    (*cmp-env* nil)
+    (*cmp-env* *cmp-env-root*)
     (*load-objects* (make-hash-table :size 128 :test #'equal))
     (*make-forms* nil)
     (*referenced-objects* (make-array 256 :adjustable t :fill-pointer 0))

src/cmp/cmpmain.lsp

@@ -214,7 +214,7 @@ after compilation."
          (*cmp-env-root* *cmp-env-root*))
 
     (with-compiler-env (compiler-conditions)
-      (setf form (set-closure-env form lexenv *cmp-env-root*))
+      (setf form (set-closure-env form lexenv *cmp-env*))
       (compiler-pass1 form)
       (compiler-pass/propagate-types)
       (let (#+(or mingw32 msvc cygwin)(*self-destructing-fasl* t))
@@ -297,7 +297,7 @@ from the C language code.  NIL means \"do not create the file\"."
          (*cmp-env-root* *cmp-env-root*))
     (with-compiler-env (compiler-conditions)
       (with-cxx-env ()
-        (setf disassembled-form (set-closure-env disassembled-form lexenv *cmp-env-root*))
+        (setf disassembled-form (set-closure-env disassembled-form lexenv *cmp-env*))
         (unwind-protect
              (progn
                (setf (symbol-function 'T3FUNCTION)

src/cmp/cmppass1-top.lsp

@@ -11,9 +11,7 @@
 
 (defun t1expr (form)
   (let* ((*current-toplevel-form* nil)
-         (*cmp-env* (if *cmp-env*
-                        (cmp-env-copy *cmp-env*)
-                        (cmp-env-root))))
+         (*cmp-env* (cmp-env-copy *cmp-env*)))
     (push (t1expr* form) *top-level-forms*)))
 
 (defvar *toplevel-forms-to-print*

src/cmp/cmputil.lsp

@@ -53,7 +53,7 @@
                         (compiler-error #'handle-compiler-error)
                         (serious-condition #'handle-compiler-internal-error))
            (mp:with-lock (mp:+load-compile-lock+)
-             (let ,+init-env-form+
+             (let* ,+init-env-form+
                (with-compilation-unit ()
                  ,@body))))
        (abort ()))