updated for version 7.3.1037
Problem: Look-behind matching is very slow on long lines.
Solution: Add a byte limit to how far back an attempt is made.
diff --git a/src/testdir/test64.ok b/src/testdir/test64.ok
index abad49f..3b53d24 100644
--- a/src/testdir/test64.ok
+++ b/src/testdir/test64.ok
@@ -719,6 +719,18 @@
OK 0 - \(a\)\(b\)\(c\)\(dd\)\(e\)\(f\)\(g\)\(h\)\(i\)\1\2\3\4\5\6\7\8\9
OK 1 - \(a\)\(b\)\(c\)\(dd\)\(e\)\(f\)\(g\)\(h\)\(i\)\1\2\3\4\5\6\7\8\9
OK 2 - \(a\)\(b\)\(c\)\(dd\)\(e\)\(f\)\(g\)\(h\)\(i\)\1\2\3\4\5\6\7\8\9
+OK 0 - <\@<=span.
+OK 1 - <\@<=span.
+OK 0 - <\@1<=span.
+OK 1 - <\@1<=span.
+OK 0 - <\@2<=span.
+OK 1 - <\@2<=span.
+OK 0 - \(<<\)\@<=span.
+OK 1 - \(<<\)\@<=span.
+OK 0 - \(<<\)\@1<=span.
+OK 1 - \(<<\)\@1<=span.
+OK 0 - \(<<\)\@2<=span.
+OK 1 - \(<<\)\@2<=span.
192.168.0.1
192.168.0.1
192.168.0.1
@@ -726,3 +738,5 @@
<T="5">Ta 5</Title>
<T="7">Ac 7</Title>
ghi
+
+xxxstart3