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

RCX-0111: `has a loop at ... , on bterm` reported on a net with no loop

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@AcKoucher is already working on this.

Since Aug 30, 2026.

rcx
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Description

Describe the bug

extract_parasitics reports a net "has a loop" when the net contains no loop at
all. Any BTERM whose pin rectangle covers two consecutive interior points of a
route triggers it. Wide, pad-style pins are the common case.

The affected RSeg is dropped, so the extracted net is quietly missing a
resistor.

Expected Behavior

Only report loops when loops actually exist

Environment
26Q3-1678-gf4b5f2d529
To Reproduce

rcx-0111-net-loop-on-bterm.tar.gz

openroad -no_splash -no_init -exit run.tcl

Observed:

[WARNING RCX-0111] Net 1 n1 has a loop at x=3.00um y=2.00um , on bterm out1.
[INFO RCX-0040] Final 3 rc segments
Relevant log output

Screenshots

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Additional Context

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