re PR middle-end/18160 (ICE on taking register variable address)

	PR middle-end/18160
	* typeck.c (cxx_mark_addressable): Issue an error if address of an
	explicit register variable is requested.

From-SVN: r90452

gcc/cp/ChangeLog

+2004-11-10  Adam Nemet  <anemet@lnxw.com>
+
+	PR middle-end/18160  
+	* typeck.c (cxx_mark_addressable): Issue an error if address of an
+	explicit register variable is requested.
+
 2004-11-10  Nathan Sidwell  <nathan@codesourcery.com>
 
 	PR c++/18143

gcc/cp/typeck.c

@@ -4343,9 +4343,16 @@ cxx_mark_addressable (tree exp)
       case CONST_DECL:
       case RESULT_DECL:
 	if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
-	    && !DECL_ARTIFICIAL (x) && extra_warnings)
-	  warning ("address requested for %qD, which is declared %<register%>",
-                   x);
+	    && !DECL_ARTIFICIAL (x))
+	  if (DECL_HARD_REGISTER (x) != 0)
+	    {
+	      error
+		("address of explicit register variable %qD requested", x);
+	      return false;
+	    }
+	  else if (extra_warnings)
+	    warning
+	      ("address requested for %qD, which is declared %<register%>", x);
 	TREE_ADDRESSABLE (x) = 1;
 	return true;