Add config.bin.target var/hint, use to decide libso{} install mode

Normally the user doesn't need to specify config.bin.target explicitly
since the cxx module will hint it. We now also have the whole set of
target's components:

bin.target.{cpu,vendor,system,version,class}

1 files changed, 2 insertions, 2 deletions

diff --git a/build2/parser.cxx b/build2/parser.cxx
index 1edc7ba..b85349b 100644
--- a/build2/parser.cxx
+++ b/build2/parser.cxx
@@ -494,8 +494,8 @@ namespace build2
                   // Note: expanding the value in the context of the scope.
                   //
                   value rhs (variable_value (t, tt));
-                  value& lhs (scope_->target_vars[*ti][move (n.value)].assign (
-                                var).first);
+                  value& lhs (
+                    scope_->target_vars[*ti][move (n.value)].assign (var));
                   value_attributes (&var, lhs, move (rhs), type::assign);
                 }
               }