1 files changed, 2 insertions, 0 deletions

diff --git a/parsing.c b/parsing.c
index 602e3de..1b2a551 100644
--- a/parsing.c
+++ b/parsing.c
@@ -56,6 +56,8 @@ char *substr(const char *head, const char *tail)
 {
         char *buf;
 
+        if (tail < head)
+                return xstrdup("");
         buf = xmalloc(tail - head + 1);
         strncpy(buf, head, tail - head);
         buf[tail - head] = '\0';