0.7.10.11:

[sbcl.git] / src / compiler / debug-dump.lisp

diff --git a/src/compiler/debug-dump.lisp b/src/compiler/debug-dump.lisp
index a69a7fc..19f6a0f 100644 (file)
--- a/src/compiler/debug-dump.lisp
+++ b/src/compiler/debug-dump.lisp
@@ -240,7 +240,7 @@
 \f
 ;;; Return a list of DEBUG-SOURCE structures containing information
 ;;; derived from INFO. Unless :BYTE-COMPILE T was specified, we always
-;;; dump the Start-Positions, since it is too hard figure out whether
+;;; dump the START-POSITIONS, since it is too hard figure out whether
 ;;; we need them or not.
 (defun debug-source-for-info (info)
   (declare (type source-info info))
@@ -277,7 +277,8 @@
 ;;; a vector whose element size is an integer multiple of output byte
 ;;; size.
 (defun coerce-to-smallest-eltype (seq)
-  (let ((maxoid #-sb-xc-host 0
+  (let ((maxoid ;; It's probably better to avoid (UNSIGNED-BYTE 0).
+               #-sb-xc-host 1 
                ;; An initial value of 255 prevents us from
                ;; specializing the array to anything smaller than
                ;; (UNSIGNED-BYTE 8), which keeps the cross-compiler's
@@ -294,7 +295,17 @@
            (frob i))
          (dovector (i seq)
            (frob i)))
-      (coerce seq `(simple-array (integer 0 ,maxoid) (*))))))
+      (let ((specializer `(unsigned-byte ,(integer-length maxoid))))
+       ;; cross-compilers beware! It would be possible for the
+       ;; upgraded-array-element-type of (UNSIGNED-BYTE 15) to be
+       ;; (SIGNED-BYTE 16), and this is completely valid by
+       ;; ANSI. However, the cross-compiler doesn't know how to dump
+       ;; SIGNED-BYTE arrays, so better make it break now if it ever
+       ;; will:
+       #+sb-xc-host
+       (aver (subtypep (upgraded-array-element-type specializer) 
+                       'unsigned-byte))
+       (coerce seq `(simple-array ,specializer (*)))))))
 \f
 ;;;; variables