The-OpenROAD-Project / The-OpenROAD-Project/OpenROAD

RCX-0114: driver pin not bound when the route only touches it, leaving a headless path

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@AcKoucher is already working on this.

Since Aug 30, 2026.

rcx
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Description

Describe the bug

When a net's driver pin is reached by routing that does not put a route
vertex inside the pin rectangle, tmg_conn fails to bind the drive term.
getStartNode() then falls back to wire point 0, and if that point carries no
terminal extract_parasitics reports that the net "does not start from an
iterm or a bterm".

The damage is silent and worse than the message suggests: the driver is
dropped from the extracted net. dbNet::isDisconnected becomes 1 and the
driver does not appear in the SPEF *CONN section, yet write_spef succeeds
and OpenROAD exits 0.

Expected Behavior

Correctly handle connectivity

Environment
26Q3-1678-gf4b5f2d529
To Reproduce

rcx-0114-net-no-start-term.tar.gz

openroad -no_splash -no_init -exit run.tcl

Observed:

[WARNING RCX-0114] Net 1 n1 does not start from an iterm or a bterm.
[INFO RCX-0040] Final 2 rc segments
Relevant log output

Screenshots

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Additional Context

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