macro - <ROM instance> does not contain any shapes or vias

[tvd040562]

Describe the bug
When running a successful ROM compilation model with openlane2, I could not get the power grid to work.

Version
Which commit are you using?

To Reproduce
What did you do to demonstrate the bug?
"MACROS": {
"rom_high": {
"instances": {
"u_mem_H": {
"location": [
50,
50
],
"orientation": "N"
}
},
"gds": [
"dir::./ROM/rom_high.gds"
],
"lef": [
"dir::./ROM/rom_high.lef"
]
},
"rom_low": {
"instances": {
"u_mem_L": {
"location": [
200,
50
],
"orientation": "N"
}
},
"gds": [
"dir::./ROM/rom_low.gds"
],
"lef": [
"dir::./ROM/rom_low.lef"
]
}
},
"VDD_NETS": "vccd1",
"GND_NETS": "vssd1",
"PDN_MACRO_CONNECTIONS": ["u_mem_H vccd1 vssd1 vccd1 vssd1",
"u_mem_L vccd1 vssd1 vccd1 vssd1"],

Expected behavior
Similar configuration using RAMs would complete the openlane run successfully

Logs
If applicable, add logs or output to help explain your problem.
[07:33:57] VERBOSE Running 'OpenROAD.GeneratePDN'… step.py:1088
[07:33:57] INFO 'FP_PDN_CFG' not explicitly set, setting it to /nix/store/m4202q1n7la2bph83v3h11q6mfrcazx4-python3-3.11.9-env/lib/python3.11/site-packages/openlane/scripts/openroad/common/pdn_cfg.tcl… openroad.py:1157
[07:33:57] VERBOSE Logging subprocess to runs/RUN_2024-09-24_07-33-47/20-openroad-generatepdn/openroad-generatepdn.log… step.py:1268
Reading OpenROAD database at '/home/lroot/labs/runs/RUN_2024-09-24_07-33-47/18-openroad-tapendcapinsertion/counter.odb'…
Reading library file at '/home/lroot/.volare/volare/sky130/versions/bdc9412b3e468c102d01b7cf6337be06ec6e9c9a/sky130A/libs.ref/sky130_fd_sc_hd/lib/sky130_fd_sc_hd__tt_025C_1v80.lib'…
Reading design constraints file at '/home/lroot/labs/counter.sdc'…
[INFO] Setting global connections...
u_mem_H matched with u_mem_H
u_mem_L matched with u_mem_L
[INFO PDN-0001] Inserting grid: stdcell_grid
[INFO PDN-0001] Inserting grid: macro - u_mem_H
[INFO PDN-0001] Inserting grid: macro - u_mem_L
[07:33:57] WARNING [PDN-0232] macro - u_mem_H does not contain any shapes or vias. openroad.py:234
[07:33:57] WARNING [PDN-0232] macro - u_mem_L does not contain any shapes or vias. openroad.py:234
[07:33:57] ERROR [PDN-0233] Failed to generate full power grid. openroad.py:232
PDN-0233
Classic - Stage 20 - Generate PDN ━━━━━━━━━━╺━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 19/76 0:00:10
[07:33:57] WARNING The following warnings were generated by the flow: flow.py:672
[07:33:57] WARNING [Checker.LintWarnings] 26 Lint warnings found. flow.py:674
[07:33:57] WARNING [OpenROAD.CheckSDCFiles] 'PNR_SDC_FILE' is not defined. Using generic fallback SDC for OpenROAD PnR steps. flow.py:674
[07:33:57] WARNING [OpenROAD.CheckSDCFiles] 'SIGNOFF_SDC_FILE' is not defined. Using generic fallback SDC for OpenROAD PnR steps. flow.py:674
[07:33:57] WARNING No libs found for macro rom_high at corner nom_tt_025C_1v80. The module will be black-boxed. (and 1 similar warnings) flow.py:674
[07:33:57] WARNING No libs found for macro rom_low at corner nom_tt_025C_1v80. The module will be black-boxed. (and 1 similar warnings) flow.py:674
[07:33:57] WARNING No libs found for macro rom_high at corner nom_ss_100C_1v60. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_low at corner nom_ss_100C_1v60. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_high at corner nom_ff_n40C_1v95. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_low at corner nom_ff_n40C_1v95. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_high at corner min_tt_025C_1v80. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_low at corner min_tt_025C_1v80. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_high at corner min_ss_100C_1v60. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_low at corner min_ss_100C_1v60. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_high at corner min_ff_n40C_1v95. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_low at corner min_ff_n40C_1v95. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_high at corner max_tt_025C_1v80. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_low at corner max_tt_025C_1v80. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_high at corner max_ss_100C_1v60. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_low at corner max_ss_100C_1v60. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_high at corner max_ff_n40C_1v95. The module will be black-boxed. flow.py:674
[07:33:57] WARNING No libs found for macro rom_low at corner max_ff_n40C_1v95. The module will be black-boxed. flow.py:674
[07:33:57] WARNING [OpenROAD.Floorplan] [ORD-2011] LEF master rom_high has no liberty cell. (and 1 similar warnings) flow.py:674
[07:33:57] WARNING [Odb.CheckMacroAntennaProperties] Cell 'rom_high' has (10) input pin(s) without antenna gate information. They might not be connected to a gate. (and 1 similar warnings) flow.py:674
[07:33:57] WARNING [OpenROAD.GeneratePDN] [PDN-0232] macro - u_mem_H does not contain any shapes or vias. (and 1 similar warnings) flow.py:674
[07:33:57] ERROR The following error was encountered while running the flow: main.py:160
OpenROAD.GeneratePDN failed with the following errors:
[PDN-0233] Failed to generate full power grid.
[07:33:57] ERROR OpenLane will now quit. main.py:161

Additional context
Add any other context about the problem here.