diff --git a/gcc/expr.c b/gcc/expr.c
index 5db0a7a85659..a150fa0d3b54 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -11828,17 +11828,22 @@ string_constant (tree arg, tree *ptr_offset, tree *mem_size, tree *decl)
 	chartype = TREE_TYPE (chartype);
       while (TREE_CODE (chartype) == ARRAY_TYPE)
 	chartype = TREE_TYPE (chartype);
-      /* Convert a char array to an empty STRING_CST having an array
-	 of the expected type and size.  */
-      if (!initsize)
-	  initsize = integer_zero_node;
 
-      unsigned HOST_WIDE_INT size = tree_to_uhwi (initsize);
-      init = build_string_literal (size, NULL, chartype, size);
-      init = TREE_OPERAND (init, 0);
-      init = TREE_OPERAND (init, 0);
+      if (INTEGRAL_TYPE_P (chartype)
+	  && TYPE_PRECISION (chartype) == TYPE_PRECISION (char_type_node))
+	{
+	  /* Convert a char array to an empty STRING_CST having an array
+	     of the expected type and size.  */
+	  if (!initsize)
+	    initsize = integer_zero_node;
 
-      *ptr_offset = integer_zero_node;
+	  unsigned HOST_WIDE_INT size = tree_to_uhwi (initsize);
+	  init = build_string_literal (size, NULL, chartype, size);
+	  init = TREE_OPERAND (init, 0);
+	  init = TREE_OPERAND (init, 0);
+
+	  *ptr_offset = integer_zero_node;
+	}
     }
 
   if (decl)