diff --git a/core/execution_units/gc_unit.sv b/core/execution_units/gc_unit.sv
index ac6865f..17db8bc 100644
--- a/core/execution_units/gc_unit.sv
+++ b/core/execution_units/gc_unit.sv
@@ -55,7 +55,7 @@ module gc_unit
 
         //Exception
         exception_interface.unit local_gc_exception,
-        exception_interface.econtrol exception [NUM_EXCEPTION_SOURCES],
+        exception_interface.econtrol exception [NUM_EXCEPTION_SOURCES-1:0],
         input logic [31:0] exception_target_pc,
 
         output logic mret,
diff --git a/core/execution_units/load_store_unit/amo_unit.sv b/core/execution_units/load_store_unit/amo_unit.sv
index 216029d..b29a9d6 100644
--- a/core/execution_units/load_store_unit/amo_unit.sv
+++ b/core/execution_units/load_store_unit/amo_unit.sv
@@ -32,7 +32,7 @@ module amo_unit
         input logic clk,
         input logic rst,
 
-        amo_interface.amo_unit agents[NUM_UNITS]
+        amo_interface.amo_unit agents[NUM_UNITS-1:0]
     );
 
     localparam RESERVATION_WIDTH = 30 - $clog2(RESERVATION_WORDS);
diff --git a/core/writeback.sv b/core/writeback.sv
index 3e5591e..0984171 100644
--- a/core/writeback.sv
+++ b/core/writeback.sv
@@ -32,7 +32,7 @@ module writeback
 
     (
         //Unit writeback
-        unit_writeback_interface.wb unit_wb[MAX_NUM_UNITS],
+        unit_writeback_interface.wb unit_wb[MAX_NUM_UNITS-1:0],
         //WB output
         output wb_packet_t wb_packet
     );