diff --git a/flow/platforms/asap7/config.mk b/flow/platforms/asap7/config.mk
index bfbb7373d5..f9b0ff1c3f 100644
--- a/flow/platforms/asap7/config.mk
+++ b/flow/platforms/asap7/config.mk
@@ -165,7 +165,7 @@ ifeq ($(ASAP7_USELVT), 1)
 
    export ABC_DRIVER_CELL         = BUFx2_ASAP7_75t_L
 
-   export FILL_CELLS              ?= "FILLERxp5_ASAP7_75t_L"
+   export FILL_CELLS              ?= FILLERxp5_ASAP7_75t_L
 
    export TAP_CELL_NAME           ?= TAPCELL_ASAP7_75t_L
 
@@ -214,7 +214,7 @@ ifeq ($(ASAP7_USESLVT), 1)
 
    export ABC_DRIVER_CELL         = BUFx2_ASAP7_75t_SL
 
-   export FILL_CELLS              ?= "FILLERxp5_ASAP7_75t_SL"
+   export FILL_CELLS              ?= FILLERxp5_ASAP7_75t_SL
 
    export TAP_CELL_NAME		  ?= TAPCELL_ASAP7_75t_SL
 
@@ -272,8 +272,8 @@ export DONT_USE_SC_LIB        = $(OBJECTS_DIR)/lib/merged.lib
 
 # IR drop estimation supply net name to be analyzed and supply voltage variable
 # For multiple nets: PWR_NETS_VOLTAGES  = "VDD1 1.8 VDD2 1.2"
-export PWR_NETS_VOLTAGES  ?= "VDD $(VOLTAGE)"
-export GND_NETS_VOLTAGES  ?= "VSS 0.0"
+export PWR_NETS_VOLTAGES  ?= VDD $(VOLTAGE)
+export GND_NETS_VOLTAGES  ?= VSS 0.0
 export IR_DROP_LAYER ?= M1
 
 # Allow empty GDS cell
diff --git a/flow/platforms/ihp-sg13g2/config.mk b/flow/platforms/ihp-sg13g2/config.mk
index 90be2e80e3..f122dd627d 100644
--- a/flow/platforms/ihp-sg13g2/config.mk
+++ b/flow/platforms/ihp-sg13g2/config.mk
@@ -117,8 +117,8 @@ export RCX_RULES = $(PLATFORM_DIR)/rcx_patterns.rules
 
 # IR drop estimation supply net name to be analyzed and supply voltage variable
 # For multiple nets: PWR_NETS_VOLTAGES  = "VDD1 1.8 VDD2 1.2"
-export PWR_NETS_VOLTAGES  ?= "VDD 1.2"
-export GND_NETS_VOLTAGES  ?= "VSS 0.0"
+export PWR_NETS_VOLTAGES  ?= VDD 1.2
+export GND_NETS_VOLTAGES  ?= VSS 0.0
 export IR_DROP_LAYER ?= Metal1
 
 # DRC Check
diff --git a/flow/platforms/nangate45/config.mk b/flow/platforms/nangate45/config.mk
index 919217f716..9d1babbef5 100644
--- a/flow/platforms/nangate45/config.mk
+++ b/flow/platforms/nangate45/config.mk
@@ -103,6 +103,6 @@ export RCX_RULES               = $(PLATFORM_DIR)/rcx_patterns.rules
 
 # IR drop estimation supply net name to be analyzed and supply voltage variable
 # For multiple nets: PWR_NETS_VOLTAGES  = "VDD1 1.8 VDD2 1.2"
-export PWR_NETS_VOLTAGES  ?= "VDD 1.1"
-export GND_NETS_VOLTAGES  ?= "VSS 0.0"
+export PWR_NETS_VOLTAGES  ?= VDD 1.1
+export GND_NETS_VOLTAGES  ?= VSS 0.0
 export IR_DROP_LAYER ?= metal1
diff --git a/flow/platforms/sky130hd/config.mk b/flow/platforms/sky130hd/config.mk
index 165cf2f3dc..24eb762fb2 100644
--- a/flow/platforms/sky130hd/config.mk
+++ b/flow/platforms/sky130hd/config.mk
@@ -133,8 +133,8 @@ export RCX_RULES = $(PLATFORM_DIR)/rcx_patterns.rules
 
 # IR drop estimation supply net name to be analyzed and supply voltage variable
 # For multiple nets: PWR_NETS_VOLTAGES  = "VDD1 1.8 VDD2 1.2"
-export PWR_NETS_VOLTAGES  ?= "VDD 1.8"
-export GND_NETS_VOLTAGES  ?= "VSS 0.0"
+export PWR_NETS_VOLTAGES  ?= VDD 1.8
+export GND_NETS_VOLTAGES  ?= VSS 0.0
 export IR_DROP_LAYER ?= met1
 
 # DRC Check
diff --git a/flow/platforms/sky130hs/config.mk b/flow/platforms/sky130hs/config.mk
index 69fbd842d6..e8d3721421 100644
--- a/flow/platforms/sky130hs/config.mk
+++ b/flow/platforms/sky130hs/config.mk
@@ -94,6 +94,6 @@ export RCX_RULES = $(PLATFORM_DIR)/rcx_patterns.rules
 
 # IR drop estimation supply net name to be analyzed and supply voltage variable
 # For multiple nets: PWR_NETS_VOLTAGES  = "VDD1 1.8 VDD2 1.2"
-export PWR_NETS_VOLTAGES  ?= "VDD 1.8"
-export GND_NETS_VOLTAGES  ?= "VSS 0.0"
+export PWR_NETS_VOLTAGES  ?= VDD 1.8
+export GND_NETS_VOLTAGES  ?= VSS 0.0
 export IR_DROP_LAYER ?= met1
diff --git a/flow/scripts/final_report.tcl b/flow/scripts/final_report.tcl
index 6900d915dd..879f74d975 100644
--- a/flow/scripts/final_report.tcl
+++ b/flow/scripts/final_report.tcl
@@ -39,7 +39,7 @@ if {[env_var_exists_and_non_empty RCX_RULES]} {
 
   # Static IR drop analysis
   if {[env_var_exists_and_non_empty PWR_NETS_VOLTAGES]} {
-    dict for {pwrNetName pwrNetVoltage}  {*}$::env(PWR_NETS_VOLTAGES) {
+    dict for {pwrNetName pwrNetVoltage} $::env(PWR_NETS_VOLTAGES) {
         set_pdnsim_net_voltage -net ${pwrNetName} -voltage ${pwrNetVoltage}
         analyze_power_grid -net ${pwrNetName} \
             -error_file $::env(REPORTS_DIR)/${pwrNetName}.rpt
@@ -48,7 +48,7 @@ if {[env_var_exists_and_non_empty RCX_RULES]} {
     puts "IR drop analysis for power nets is skipped because PWR_NETS_VOLTAGES is undefined"
   }
   if {[env_var_exists_and_non_empty GND_NETS_VOLTAGES]} {
-    dict for {gndNetName gndNetVoltage}  {*}$::env(GND_NETS_VOLTAGES) {
+    dict for {gndNetName gndNetVoltage} $::env(GND_NETS_VOLTAGES) {
         set_pdnsim_net_voltage -net ${gndNetName} -voltage ${gndNetVoltage}
         analyze_power_grid -net ${gndNetName} \
             -error_file $::env(REPORTS_DIR)/${gndNetName}.rpt