From 6d315552366f9cf9190f14ac70dba10f893ec484 Mon Sep 17 00:00:00 2001
From: Peter Barker <pbarker@barker.dropbear.id.au>
Date: Mon, 13 Jan 2025 16:16:17 +1100
Subject: [PATCH] AP_HAL_SITL: remove command-line option enabling synthetic
 clock

it's always on, all the time

this has always been set for many years
---
 libraries/AP_HAL_SITL/SITL_State.cpp   | 7 ++-----
 libraries/AP_HAL_SITL/SITL_State.h     | 2 --
 libraries/AP_HAL_SITL/SITL_cmdline.cpp | 4 +---
 3 files changed, 3 insertions(+), 10 deletions(-)

diff --git a/libraries/AP_HAL_SITL/SITL_State.cpp b/libraries/AP_HAL_SITL/SITL_State.cpp
index 06fe08506f..736e7091e8 100644
--- a/libraries/AP_HAL_SITL/SITL_State.cpp
+++ b/libraries/AP_HAL_SITL/SITL_State.cpp
@@ -106,10 +106,8 @@ void SITL_State::_sitl_setup()
         _sitl->rcin_port = _rcin_port;
     }
 
-    if (_synthetic_clock_mode) {
-        // start with non-zero clock
-        hal.scheduler->stop_clock(1);
-    }
+    // start with non-zero clock
+    hal.scheduler->stop_clock(1);
 }
 
 
@@ -284,7 +282,6 @@ void SITL_State::_fdm_input_local(void)
 
     set_height_agl();
 
-    _synthetic_clock_mode = true;
     _update_count++;
 }
 
diff --git a/libraries/AP_HAL_SITL/SITL_State.h b/libraries/AP_HAL_SITL/SITL_State.h
index b5452aceda..4a202493a6 100644
--- a/libraries/AP_HAL_SITL/SITL_State.h
+++ b/libraries/AP_HAL_SITL/SITL_State.h
@@ -87,8 +87,6 @@ private:
     uint16_t _fg_view_port;
     uint16_t _irlock_port;
 
-    bool _synthetic_clock_mode;
-
     bool _use_rtscts;
     bool _use_fg_view;
     
diff --git a/libraries/AP_HAL_SITL/SITL_cmdline.cpp b/libraries/AP_HAL_SITL/SITL_cmdline.cpp
index 042bb2ce7f..2d747ac228 100644
--- a/libraries/AP_HAL_SITL/SITL_cmdline.cpp
+++ b/libraries/AP_HAL_SITL/SITL_cmdline.cpp
@@ -209,7 +209,6 @@ void SITL_State::_parse_command_line(int argc, char * const argv[])
     float speedup = 1.0f;
     float sim_rate_hz = 0;
     _instance = 0;
-    _synthetic_clock_mode = false;
     // default to CMAC
     const char *home_str = nullptr;
     const char *model_str = nullptr;
@@ -422,7 +421,7 @@ void SITL_State::_parse_command_line(int argc, char * const argv[])
             _set_param_default(gopt.optarg);
             break;
         case 'S':
-            _synthetic_clock_mode = true;
+            printf("Ignoring stale command-line parameter '-S'");
             break;
         case 'O':
             home_str = gopt.optarg;
@@ -586,7 +585,6 @@ void SITL_State::_parse_command_line(int argc, char * const argv[])
             sitl_model->set_instance(_instance);
             sitl_model->set_autotest_dir(autotest_dir);
             sitl_model->set_config(config);
-            _synthetic_clock_mode = true;
             break;
         }
     }