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Hello <@U016EM8L91B>, I've been working with magic...
# magic
v
Hello @Tim Edwards, I've been working with magic using tcl files for generating layouts by using subcells. After flattening and saving the file, when I load it this message appears. I don't know if it is significant, as the layout seems to be ok. Nonetheless, when I do extraction of the parasitics, I have a slight change (1 cap changes its value). Also, it is worth noting that if I start magic with the tcl file directly by writing the command line 
PDKPATH="${PDK_ROOT}/sky130A" magic -dnull -noconsole mag_files/waffles_nmos.tcl
, 1 cap and 1 resistor disappear from the extracted SPICE file. Inside the attached 
mag_files/
folder you can find the 
.tcl
file that calls the cells from 
waffle_cells/
. The file is thought to be run from a parent folder that has this 2 folders inside. Hope you're doing well 😄
waffle_cells.zipmag_files.zip
t
The error comes from the "mask hints" property and may be a string buffer overflow. Since it's a property, you won't see it visually in the layout, but I'm pretty sure it didn't read in correctly. I will track down the problem.
I fixed the error in magic, but be advised that your use of the "mask hint" property is inadvisable. Instead of being in the database, any geometry specified by a mask hint will be literally parsed out of a string representation, so magic will slow to a crawl doing anything with this layout like generating GDS. It works best to keep "mask hints" as simple as possible, so don't add a mask hint for every subcell, but just put one HVI implant layer (and one HVNTM implant layer) over the entire layout, in the top level cell.
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