klayoutmatthias
commented
2 months ago The implemented solution will show the cell in the mentioned case, but it is kind of volatile. You can create a new top cell and add the original cell as a child cell. This will make it a valid PCell instance again. You can also convert the PCell into a static cell.
However, as soon as you create other cells and instances, at some point the PCell will be cleaned up, like all PCells are when they are not used.
The following file is a single PCell instance:
https://github.com/IHP-GmbH/IHP-Open-DesignLib/blob/main/ElemRV/design_data/src/macros/sealring/sealring_2015x2014.gds.gz
Formally this is not legal as a PCell only exists through an instance. However it appears to be possible to save a PCell variant and receive such a file. This file behaves weirdly. It does not show any layout and when trying to add a new cell, KLayout complains that no layout is opened.
The expected behavior is that in such a case, the cell is loaded and converted to a static cell.
In addition, saving a PCell variant to a file should give a warning at least and if intended, the cell should be saved without context to make it a static cell.
The workaround is to save the cell without context (use "Save As" and disable context in the writer options) or to convert it to a static cell before saving.