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# Can these warnings be removed?
Tool: OpenSTA
Subcategory: Warning handling
## Conversation
### oharboe
I've found myself ignoring warnings when I shouldn't...
In that regard, it would be helpful to fix some warnings that are always there, so I pay more attention...
Can these be fixed?
```
[WARNING STA-0164] /OpenROAD-flow-scripts/flow/platforms/asap7/lib/asap7sc7p5t_SIMPLE_RVT_TT_nldm_211120.lib.gz line 13178, timing group from output port.
[WARNING STA-0164] /OpenROAD-flow-scripts/flow/platforms/asap7/lib/asap7sc7p5t_SIMPLE_RVT_TT_nldm_211120.lib.gz line 13211, timing group from output port.
[WARNING STA-0164] /OpenROAD-flow-scripts/flow/platforms/asap7/lib/asap7sc7p5t_SIMPLE_RVT_TT_nldm_211120.lib.gz line 13244, timing group from output port.
[WARNING STA-0164] /OpenROAD-flow-scripts/flow/platforms/asap7/lib/asap7sc7p5t_SIMPLE_RVT_TT_nldm_211120.lib.gz line 13277, timing group from output port.
[WARNING STA-0164] /OpenROAD-flow-scripts/flow/platforms/asap7/lib/asap7sc7p5t_SIMPLE_RVT_TT_nldm_211120.lib.gz line 13310, timing group from output port.
[WARNING STA-0164] /OpenROAD-flow-scripts/flow/platforms/asap7/lib/asap7sc7p5t_SIMPLE_RVT_TT_nldm_211120.lib.gz line 13343, timing group from output port.
[WARNING STA-0164] /OpenROAD-flow-scripts/flow/platforms/asap7/lib/asap7sc7p5t_SIMPLE_RVT_TT_nldm_211120.lib.gz line 13376, timing group from output port.
[WARNING STA-0164] /OpenROAD-flow-scripts/flow/platforms/asap7/lib/asap7sc7p5t_SIMPLE_RVT_TT_nldm_211120.lib.gz line 14772, timing group from output port.
[WARNING STA-0164] /OpenROAD-flow-scripts/flow/platforms/asap7/lib/asap7sc7p5t_SIMPLE_RVT_TT_nldm_211120.lib.gz line 14805, timing group from output port.
[WARNING STA-0164] /OpenROAD-flow-scripts/flow/platforms/asap7/lib/asap7sc7p5t_SIMPLE_RVT_TT_nldm_211120.lib.gz line 14838, timing group from output port.
```
### rovinski
They cannot, the warnings are due to the structure of the cells in the PDK and the way they were characterized into a timing model. You can, however, stop the warnings from showing up by using `suppress_message STA 164`.
### vijayank88
I have discussed about this `WARNING STA-016` month back with Tom. Replied:
```
The output to output timing edges in the liberty cause this warning.
If it's just this one cell, you could add it to the don't use list.
I think this warning means the timing will be less accurate.
If you are doing experiments it may also be safe to ignore.
```