commit 274a76323cb9998df0c1a4dc5b1820d70e0a1886
author Benjamin Peterson <benjamin@python.org> Sun Sep 18 23:41:11 2016 -0700
committer Benjamin Peterson <benjamin@python.org> Sun Sep 18 23:41:11 2016 -0700
tree abad3817c7c2a6caec69f1c2b856d45d60f974bb
parent b00cc8392a10f9ae457f9de4625aa8842c9b6a18

properly handle the single null-byte file (closes #24022)

Parser/tokenizer.c

diff --git a/Parser/tokenizer.c b/Parser/tokenizer.c
index 7e4a300..4fdbad9 100644
--- a/Parser/tokenizer.c
+++ b/Parser/tokenizer.c
@@ -951,7 +951,7 @@
                 else {
                     tok->done = E_OK;
                     tok->inp = strchr(tok->buf, '\0');
-                    done = tok->inp[-1] == '\n';
+                    done = tok->inp == tok->buf || tok->inp[-1] == '\n';
                 }
             }
             else {