Number: 1722
Title: dot hangs on some input with tailport&headport&same rank
Submitter: Oisín Mac Fhearaí
Date: Thu Jul 23 18:44:06 2009
Subsys: Dot
Version: 2.24
System: *-*-*
Severity: minor
The following input (a reduction of an example of dot syntax on wikipedia) causes dot to hang indefinitely (or... at least for 3 or 4 minutes now, which is effectively forever!) on my dual-core machine. By removing any element from the sample input, dot will process the file in less than a second.
digraph g {
	A1 -> B1
	A2 -> B2
	A3 -> B3
	A2 -> A3
	B1 -> B3 [label="xyz" tailport=s headport=s]
	B2 -> B3
	{ rank=same; B1 B2 B3 } }
[erg] The base problem is that the spline router produces an incorrect route, which goes wildly outside the given boxes. The code recognizes something has gone wrong. This is usually a case where increased sampling helps but since a line segment is involved, finer sampling doesn't help.
Owner: *
Status: *