tool_name: OpenROAD

severity: ERROR

log_line: [ERROR] ERROR: routing congestion overflow in region (450,600)-(550,700), overflow=18

fix_hint: Reduce placement density or add routing blockage in congested region


log_line: WNS: -0.85 worst negative slack

module: adder

fix_hint: Add pipeline register between adder stages or upsize driver cells on critical path


log_line: [ERROR] FATAL: timing closure failed, 4 paths violate constraints

fix_hint: Run incremental ECO timing optimization or relax clock constraint


log_line: [ERROR] ERROR: metal spacing violation at (324, 512), layer M2, required=0.14um actual=0.10um

fix_hint: Increase spacing between metal traces at coordinates (324,512) on M2 layer


severity: WARNING

log_line: [WARNING] WARNING: multi-driven net_reset_sync driven by 2 drivers: rst_gen/out, por_cell/rst

issue_type: MULTIDRIVEN

fix_hint: Use OR gate or MUX to combine reset sources; remove one duplicate driver


log_line: [WARNING] CAUTION: latch inferred unexpected in module arbitrator, signal grant_r

module: arbitrator

fix_hint: Add default assignment to grant_r or use always_ff with full condition coverage


log_line: [ERROR] ERROR: combinational loop detected in module scheduler: path req->grant->req

module: scheduler

fix_hint: Break combinational loop by inserting a register on the req->grant->req path


log_line: [WARNING] WARNING: placement density 0.92 exceeds recommended 0.80

fix_hint: Increase die area or reduce cell count to bring placement density below 0.80


log_line: [WARNING] WARNING: clock skew 120ps exceeds target 50ps on path clk_div2

fix_hint: Rebalance clock tree buffers on clk_div2 path to reduce skew below 50ps


log_line: [WARNING] WARNING: IR drop 85mV on power domain VDD_CORE exceeds limit 50mV

fix_hint: Add power straps or increase VDD_CORE rail width to reduce IR drop below 50mV


log_line: [ERROR] WNS: -0.42 Timing violation detected in module adder

fix_hint: Upsize drive strength on critical path cells in adder module


log_line: FATAL: latch inferred unexpected in module fsm

module: fsm

fix_hint: Add default case or else branch in FSM always block


log_line: [WARNING] multi-driven net_data_bus found at file top.v line 42

fix_hint: Identify and remove duplicate driver on net_data_bus at top.v:42


log_line: [WARNING] TNS: -1.23 total negative slack

fix_hint: Run global timing optimization to fix all negative slack paths