# Sfdp crash, regression in 15.1.1

**URL:** <https://forum.graphviz.org/t/sfdp-crash-regression-in-15-1-1/3392>\
**Category:** Uncategorized\
**Created:** [August 12, 2026, 10:25am UTC](https://forum.graphviz.org/t/sfdp-crash-regression-in-15-1-1/3392 "2026-08-12T10:25:13Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![gertburger](https://sea2.discourse-cdn.com/graphviz/user_avatar/forum.graphviz.org/gertburger/32/2143_2.png) [@gertburger](https://forum.graphviz.org/u/gertburger)\
**Post date:** [August 12, 2026, 10:25am UTC](https://forum.graphviz.org/t/sfdp-crash-regression-in-15-1-1/3392/1 "2026-08-12T10:25:13Z")

</div>

Given the graph `test.gv` with content:

```auto
digraph {
  n0 -> n1; n0 -> n2; n0 -> n3; n0 -> n4;
  n0 -> n5; n0 -> n6; n0 -> n7; n0 -> n8;
  n0 -> n9; n0 -> n10; n0 -> n11; n0 -> n12;
  n13 -> n14; n13 -> n7;
  n15 -> n16; n15 -> n17; n15 -> n18;
  n19 -> n20; n19 -> n21; n19 -> n18;
  n19 -> n2; n19 -> n22; n19 -> n23;
}

```

then

```auto
❯ sfdp -Tsvg test.gv
free(): invalid size
[1] 1131228 abort (core dumped) sfdp -Tsvg test.gv

```

Works fine in 15.1.0.

Sorry for reporting this here but creating a gitlab account is too much friction after they started requiring CC details for account creation.

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<div class="post-metadata">

**Author:** ![steveroush](https://avatars.discourse-cdn.com/v4/letter/s/a9adbd/32.png) [@steveroush](https://forum.graphviz.org/u/steveroush)\
**Post date:** [August 12, 2026, 2:39pm UTC](https://forum.graphviz.org/t/sfdp-crash-regression-in-15-1-1/3392/2 "2026-08-12T14:39:22Z")

</div>

Thanks for the report.  
An issues has been created ([new (15.1.5) bug in sfdp [abort (core dumped)] (#2852) · Issues · graphviz / graphviz · GitLab](https://gitlab.com/graphviz/graphviz/-/work_items/2852))

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<div class="post-metadata">

**Author:** ![smattr](https://sea2.discourse-cdn.com/graphviz/user_avatar/forum.graphviz.org/smattr/32/85_2.png) [@smattr](https://forum.graphviz.org/u/smattr)\
**Post date:** [August 13, 2026, 7:10am UTC](https://forum.graphviz.org/t/sfdp-crash-regression-in-15-1-1/3392/3 "2026-08-13T07:10:27Z")

</div>

Thanks for reporting and apologies for the inconvenience. I believe I have a fix. Just running it through CI now, [https://gitlab.com/smattr/graphviz/-/commits/smattr/gitlab-2852](https://gitlab.com/smattr/graphviz/-/commits/smattr/gitlab-2852).

Personally I’m happy to accept Graphviz bug reports through any channel (Gitlab, here, emailed to me, shouted at me on the street, …).

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<div class="post-metadata">

**Author:** ![smattr](https://sea2.discourse-cdn.com/graphviz/user_avatar/forum.graphviz.org/smattr/32/85_2.png) [@smattr](https://forum.graphviz.org/u/smattr)\
**Post date:** [September 5, 2026, 1:09am UTC](https://forum.graphviz.org/t/sfdp-crash-regression-in-15-1-1/3392/4 "2026-09-05T01:09:59Z")

</div>

For reference, the fix for this landed in Graphviz 16.1.0.