egencache: ensure correct porttrees

The GenCache class assumes that portdb.porttrees[0] is the desired
tree, so assert that it is true. The behavior should have already been
correct, since PORTDIR_OVERLAY was already set to an empty string when
necessary.

1 files changed, 2 insertions, 0 deletions

diff --git a/bin/egencache b/bin/egencache
index 01eadf053..22ce8ec33 100755
--- a/bin/egencache
+++ b/bin/egencache
@@ -864,6 +864,8 @@ def egencache_main(args):
 
 		# Limit ebuilds to the specified repo.
 		portdb.porttrees = [repo_path]
+	else:
+		portdb.porttrees = [portdb.porttree_root]
 
 	ret = [os.EX_OK]