1 files changed, 59 insertions, 14 deletions

diff --git a/src/print.c b/src/print.c
index b5e45438577..8420f8075a5 100644
--- a/src/print.c
+++ b/src/print.c
@@ -2036,8 +2036,9 @@ print_object (Lisp_Object obj, register Lisp_Object printcharfun, int escapeflag
           PRINTCHAR ('>');
           break;
 
-      /* Remaining cases shouldn't happen in normal usage, but let's print
-         them anyway for the benefit of the debugger.  */
+          /* Remaining cases shouldn't happen in normal usage, but let's
+             print them anyway for the benefit of the debugger.  */
+
         case Lisp_Misc_Free:
           strout ("#<misc free cell>", -1, -1, printcharfun);
           break;
@@ -2048,20 +2049,28 @@ print_object (Lisp_Object obj, register Lisp_Object printcharfun, int escapeflag
             struct Lisp_Save_Value *v = XSAVE_VALUE (obj);
 
             strout ("#<save-value ", -1, -1, printcharfun);
-            if (v->dogc)
+
+            if (v->area)
               {
-                int lim = min (v->integer, 8);
-                
-                /* Try to print up to 8 objects we have saved.  Although
-                   valid_lisp_object_p is slow, this shouldn't be a real
-                   bottleneck because such a saved values are quite rare.  */
+                ptrdiff_t amount = v->data[1].integer;
+
+#if GC_MARK_STACK
+
+                /* If GC_MARK_STACK, valid_lisp_object_p is quite reliable,
+                   and so we try to print up to 8 objects we have saved.
+                   Although valid_lisp_object_p is slow, this shouldn't be
+                   a real bottleneck because we do not use this code under
+                   normal circumstances.  */
 
-                i = sprintf (buf, "with %"pD"d objects", v->integer);
+                int limit = min (amount, 8);
+                Lisp_Object *area = v->data[0].pointer;
+
+                i = sprintf (buf, "with %"pD"d objects", amount);
                 strout (buf, i, i, printcharfun);
 
-                for (i = 0; i < lim; i++)
+                for (i = 0; i < limit; i++)
                   {
-                    Lisp_Object maybe = ((Lisp_Object *) v->pointer)[i];
+                    Lisp_Object maybe = area[i];
 
                     if (valid_lisp_object_p (maybe) > 0)
                       {
@@ -2071,13 +2080,49 @@ print_object (Lisp_Object obj, register Lisp_Object printcharfun, int escapeflag
                     else
                       strout (" <invalid>", -1, -1, printcharfun);
                   }
-                if (i == lim && i < v->integer)
+                if (i == limit && i < amount)
                   strout (" ...", 4, 4, printcharfun);
+
+#else /* not GC_MARK_STACK */
+
+                /* If !GC_MARK_STACK, we have no reliable way to find
+                   whether Lisp_Object pointers points to an initialized
+                   objects, and so we do not ever trying to print them.  */
+
+                i = sprintf (buf, "with %"pD"d objects", amount);
+                strout (buf, i, i, printcharfun);
+
+#endif /* GC_MARK_STACK */
               }
             else
               {
-                i = sprintf (buf, "ptr=%p int=%"pD"d", v->pointer, v->integer);
-                strout (buf, i, i, printcharfun);
+                /* Print each `data[N]' slot according to its type.  */
+
+#define PRINTX(index)                                                   \
+  do {                                                                  \
+    i = 0;                                                              \
+    if (v->type ## index == SAVE_UNUSED)                                \
+      i = sprintf (buf, "<unused>");                                    \
+    else if (v->type ## index == SAVE_INTEGER)                          \
+      i = sprintf (buf, "<integer %"pD"d>", v->data[index].integer);    \
+    else if (v->type ## index == SAVE_POINTER)                          \
+      i = sprintf (buf, "<pointer %p>", v->data[index].pointer);        \
+    else /* SAVE_OBJECT */                                              \
+      print_object (v->data[index].object, printcharfun, escapeflag);   \
+    if (i)                                                              \
+      strout (buf, i, i, printcharfun);                                 \
+  } while (0)
+
+                PRINTX (0);
+                PRINTCHAR (' ');
+                PRINTX (1);
+                PRINTCHAR (' ');
+                PRINTX (2);
+                PRINTCHAR (' ');
+                PRINTX (3);
+
+#undef PRINTX
+
               }
             PRINTCHAR ('>');
           }