From 6d7739e7e8e8864dc5eb79e42b6c2675cd7733ca Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Sch=C3=A4pers?= <bjoern@hazardy.de>
Date: Thu, 5 Jun 2025 10:09:51 +0200
Subject: [PATCH] Don't fail on nearly blank lines

If a line only contains tabs the word will be an empty string. And then
is_prefix_of does match on rule, beacuse it's substring of length 0 is
also an empty string. Subsequently the parsing of the rule fails with an
exception.
---
 src/tz.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/tz.cpp b/src/tz.cpp
index 15c9f5d..c3c7a52 100644
--- a/src/tz.cpp
+++ b/src/tz.cpp
@@ -3838,6 +3838,10 @@ init_tzdb()
                 std::istringstream in(line);
                 std::string word;
                 in >> word;
+                if (word.empty())
+                {
+                  continue;
+                }
                 tolower(word);
                 if (is_prefix_of(word, "rule"))
                 {