c-typeck.c (build_unary_op): Invoke non_lvalue.

        * c-typeck.c (build_unary_op) [CONVERT_EXPR]: Invoke non_lvalue.
	* gcc.dg/lvalue1.c: New.

From-SVN: r52812

gcc/ChangeLog

+2002-04-26  Richard Henderson  <rth@redhat.com>
+
+	PR c/5225
+	* c-typeck.c (build_unary_op) [CONVERT_EXPR]: Invoke non_lvalue.
+
 2002-04-26  Mark Mitchell  <mark@codesourcery.com>
 
 	PR bootstrap/6445

gcc/c-typeck.c

@@ -2759,6 +2759,7 @@ build_unary_op (code, xarg, flag)
 	}
       else if (!noconvert)
 	arg = default_conversion (arg);
+      arg = non_lvalue (arg);
       break;
 
     case NEGATE_EXPR:

gcc/testsuite/gcc.dg/lvalue1.c

+/* PR c/5225 */
+/* { dg-do compile } */
+
+int main()
+{
+  int i;
+  +i = 1;	/* { dg-error "invalid lvalue in assignment" } */
+  return 0;
+}