Use relative line number in unroll-5.c

2017-12-26  Tom de Vries  <tom@codesourcery.com>

	* c-c++-common/unroll-5.c: Use relative line number.

From-SVN: r256002

gcc/testsuite/ChangeLog

+2017-12-26  Tom de Vries  <tom@codesourcery.com>
+
+	* c-c++-common/unroll-5.c: Use relative line number.
+
 2017-12-23  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/83553

gcc/testsuite/c-c++-common/unroll-5.c

@@ -19,7 +19,7 @@ void test (void)
     bar(i);
 
   #pragma GCC unroll j	/* { dg-error "requires an assignment-expression that evaluates to a non-negative integral constant less than" } */
-                        /* { dg-error "cannot appear in a constant-expression|is not usable in a constant expression" "" { target c++ } 21 } */
+                        /* { dg-error "cannot appear in a constant-expression|is not usable in a constant expression" "" { target c++ } .-1 } */
   for (unsigned long i = 1; i <= 8; ++i)
     bar(i);