diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index fecac218bf5a..023414679c81 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2003-04-21  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
+
+	* expr.c (store_constructor): Set RTX_UNCHANGING_P if readonly_field_p
+	before clearing.
+
 2003-04-21  Mark Mitchell  <mark@codesourcery.com>
 
 	* config/i386/winnt.c (i386_pe_mark_dllimport): Make the new RTL
diff --git a/gcc/expr.c b/gcc/expr.c
index abf0875c849a..f87f9c900ff3 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -4899,7 +4899,15 @@ store_constructor (exp, target, cleared, size)
 		   || ((HOST_WIDE_INT) GET_MODE_SIZE (GET_MODE (target))
 		       == size)))
 	{
-	  clear_storage (target, GEN_INT (size));
+	  rtx xtarget = target;
+
+	  if (readonly_fields_p (type))
+	    {
+	      xtarget = copy_rtx (xtarget);
+	      RTX_UNCHANGING_P (xtarget) = 1;
+	    }
+
+	  clear_storage (xtarget, GEN_INT (size));
 	  cleared = 1;
 	}