Simplify (and robustify) regular PACKing

[sbcl.git] / src / compiler / constantp.lisp

diff --git a/src/compiler/constantp.lisp b/src/compiler/constantp.lisp
index 85bb5b8..d06d226 100644 (file)
--- a/src/compiler/constantp.lisp
+++ b/src/compiler/constantp.lisp
@@ -29,7 +29,7 @@
 
 (defun %constantp (form environment envp)
   (let ((form (if envp
-                  (sb!xc:macroexpand form environment)
+                  (%macroexpand form environment)
                   form)))
     (typecase form
       ;; This INFO test catches KEYWORDs as well as explicitly
@@ -45,11 +45,23 @@
 
 (defun %constant-form-value (form environment envp)
   (let ((form (if envp
-                  (sb!xc:macroexpand form environment)
+                  (%macroexpand form environment)
                   form)))
     (typecase form
       (symbol
-       (symbol-value form))
+       ;; KLUDGE: superficially, this might look good enough: we grab
+       ;; the value from the info database, and if it isn't there (or
+       ;; is NIL, but hey) we use the host's value.  This works for
+       ;; MOST-POSITIVE-FIXNUM and friends, but still fails for
+       ;; float-related constants, where there is in fact no guarantee
+       ;; that we can represent our target value at all in the host,
+       ;; so we don't try.  We should rework all uses of floating
+       ;; point so that we never try to use a host's value, and then
+       ;; make some kind of assertion that we never attempt to take
+       ;; a host value of a constant in the CL package.
+       #+sb-xc-host (or (info :variable :xc-constant-value form)
+                        (symbol-value form))
+       #-sb-xc-host (symbol-value form))
       (list
        (if (special-operator-p (car form))
            (constant-special-form-value form environment envp)