glr.cc: be more alike lalr1.cc

[Akim Demaille]

commit 626d2f2dcab92584c0324c93c6cc7294c7bf740c
Author: Akim Demaille <address@hidden>
Date:   Sat Jan 19 17:42:48 2019 +0100

    glr.cc: be more alike lalr1.cc

diff --git a/data/skeletons/glr.cc b/data/skeletons/glr.cc
index 7d333bf2..778c65b8 100644
--- a/data/skeletons/glr.cc
+++ b/data/skeletons/glr.cc
@@ -246,9 +246,12 @@ b4_percent_code_get([[requires]])[
 #include <stdexcept>
 #include <string>
 
-]m4_ifdef([b4_location_file],
+]b4_cxx_portability[
+]m4_ifdef([b4_location_include],
           [[# include ]b4_location_include])[
+]b4_variant_if([b4_variant_includes])[
 
+]b4_attribute_define[
 ]b4_null_define[
 
 // Whether we are compiled with exception support.
@@ -263,6 +266,7 @@ b4_percent_code_get([[requires]])[
 ]b4_YYDEBUG_define[
 
 ]b4_namespace_open[
+
 ]b4_bison_locations_if([m4_ifndef([b4_location_file],
                                   [b4_location_define])])[