fold-const.c (tree_expr_nonzero_p): Use get_base_address before assuming an ADDR_EXPR is non-null.

        * fold-const.c (tree_expr_nonzero_p): Use get_base_address before
        assuming an ADDR_EXPR is non-null.
cp/
        * class.c (fixed_type_or_null): Use get_base_address before
        assuming an ADDR_EXPR is non-null.

From-SVN: r86788

gcc/ChangeLog

+2004-08-30  Richard Henderson  <rth@redhat.com>
+
+	* fold-const.c (tree_expr_nonzero_p): Use get_base_address before
+	assuming an ADDR_EXPR is non-null.
+
 2004-08-30  Jason Merrill  <jason@redhat.com>
 
 	* gthr-posix.h, gthr-dce.h: Add #pragma weaks.

gcc/cp/ChangeLog

+2004-08-30  Richard Henderson  <rth@redhat.com>
+
+	* class.c (fixed_type_or_null): Use get_base_address before
+	assuming an ADDR_EXPR is non-null.
+
 2004-08-30  Nathan Sidwell  <nathan@codesourcery.com>
 
 	* name-lookup.c (pop_binding, pushdecl,

gcc/cp/class.c

@@ -5238,9 +5238,17 @@ fixed_type_or_null (tree instance, int* nonnull, int* cdtorp)
       return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
 
     case ADDR_EXPR:
+      instance = TREE_OPERAND (instance, 0);
       if (nonnull)
-	*nonnull = 1;
-      return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull, cdtorp);
+	{
+	  /* Just because we see an ADDR_EXPR doesn't mean we're dealing
+	     with a real object -- given &p->f, p can still be null.  */
+	  tree t = get_base_address (instance);
+	  /* ??? Probably should check DECL_WEAK here.  */
+	  if (t && DECL_P (t))
+	    *nonnull = 1;
+	}
+      return fixed_type_or_null (instance, nonnull, cdtorp);
 
     case COMPONENT_REF:
       /* If this component is really a base class reference, then the field

gcc/fold-const.c

@@ -9582,11 +9582,22 @@ tree_expr_nonzero_p (tree t)
       break;
 
    case ADDR_EXPR:
-      /* Weak declarations may link to NULL.  */
-      if (DECL_P (TREE_OPERAND (t, 0)))
-	return !DECL_WEAK (TREE_OPERAND (t, 0));
-      /* Constants and all other cases are never weak.  */
-      return true;
+      {
+	tree base = get_base_address (TREE_OPERAND (t, 0));
+
+	if (!base)
+	  return false;
+
+	/* Weak declarations may link to NULL.  */
+	if (DECL_P (base))
+	  return !DECL_WEAK (base);
+
+	/* Constants are never weak.  */
+	if (TREE_CODE_CLASS (TREE_CODE (base)) == 'c')
+	  return true;
+
+	return false;
+      }
 
     case COND_EXPR:
       return (tree_expr_nonzero_p (TREE_OPERAND (t, 1))