[PATCH 2/7] glr.cc: fatal if using api.token.ctor without variants

[Theophile Ranquet]

* data/glr.cc: Here.
---
 data/glr.cc | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/data/glr.cc b/data/glr.cc
index 1688d3d..0d7e03a 100644
--- a/data/glr.cc
+++ b/data/glr.cc
@@ -43,6 +43,14 @@
 #   user must initialize the first positions (in particular the
 #   filename member).
 
+b4_token_ctor_if([b4_variant_if([],
+                                
[b4_fatal_at(b4_percent_define_get_loc(api.token.constructor),
+                                             [cannot use '%s' without '%s'],
+                                             [%define api.token.constructor],
+                                             [%define api.value.type variant])
+                                )])],
+                [])
+
 # We require a pure interface.
 m4_define([b4_pure_flag],      [1])
 
-- 
1.8.1