Error when a recursive variable references itself (#205)

* Error when a recursive variable references itself

Identify when a recursive variable references itself and print the
appropriate error message.

Fixes: https://github.com/google/kati/issues/204

* trigger GitHub actions

* trigger GitHub actions

1 files changed, 2 insertions, 1 deletions

diff --git a/src/dep.cc b/src/dep.cc
index 6fdfd62..37a4f97 100644
--- a/src/dep.cc
+++ b/src/dep.cc
@@ -692,7 +692,8 @@ class DepBuilder {
             if (!s->empty())
               *s += ' ';
             new_var->Eval(ev_, s.get());
-            new_var = new SimpleVar(*s, old_var->Origin(), frame.Current());
+            new_var =
+                new SimpleVar(*s, old_var->Origin(), frame.Current(), n->loc);
           }
         } else if (var->op() == AssignOp::QUESTION_EQ) {
           Var* old_var = ev_->LookupVar(name);