refactor(platform): out-line ModuleParams setParent and destructor to save flash (#28321)

Both were defined inline in the header, so the List add/remove bodies
were duplicated into the constructor and destructor of every one of the
150+ ModuleParams-derived classes. Construction and destruction are cold
paths; a call is smaller at each site.

Two consumers reach ModuleParams without px4_platform on the link line
and now need the definitions explicitly: health_and_arming_checks (the
functional-ModeManagement test only pulls it in transitively through
modules__commander, after px4_platform) and the failsafe_web emscripten
build, which compiles module_params.cpp directly.

The smaller constructors let the compiler fully inline the defaulted
FlightTaskDescend constructor on the ITCM boards, so its entry is
dropped from their linker scripts.

Saves 3968 B of .text on px4_fmu-v6x_default.


Assisted-by: Claude:claude-fable-5

Signed-off-by: Jacob Dahl <dahl.jakejacob@gmail.com>
Co-authored-by: Balduin <balduin@auterion.com>

boards/nxp/mr-tropic/nuttx-config/scripts/itcm_functions_includes.ld

@@ -625,7 +625,6 @@
 *(.text._ZN36do_not_explicitly_use_this_namespace5ParamIfLN3px46paramsE919EEC1Ev) /* itcm-check-ignore */
 *(.text._ZN22MavlinkStreamHeartbeat8get_sizeEv)
 *(.text._ZN6matrix6MatrixIfLj3ELj1EEdVEf)
-*(.text._ZN17FlightTaskDescendC1Ev)
 *(.text._ZN26MavlinkStreamCameraTrigger8get_sizeEv)
 *(.text.iob_navail)
 *(.text._ZN12FailsafeBase25removeNonActivatedActionsEv)

boards/nxp/tropic-community/nuttx-config/scripts/itcm_functions_includes.ld

@@ -625,7 +625,6 @@
 *(.text._ZN36do_not_explicitly_use_this_namespace5ParamIfLN3px46paramsE919EEC1Ev) /* itcm-check-ignore */
 *(.text._ZN22MavlinkStreamHeartbeat8get_sizeEv)
 *(.text._ZN6matrix6MatrixIfLj3ELj1EEdVEf)
-*(.text._ZN17FlightTaskDescendC1Ev)
 *(.text._ZN26MavlinkStreamCameraTrigger8get_sizeEv)
 *(.text.iob_navail)
 *(.text._ZN12FailsafeBase25removeNonActivatedActionsEv)

boards/px4/fmu-v6xrt/nuttx-config/scripts/itcm_functions_includes.ld

@@ -639,7 +639,6 @@
 *(.text._ZN36do_not_explicitly_use_this_namespace5ParamIfLN3px46paramsE919EEC1Ev) /* itcm-check-ignore */
 *(.text._ZN22MavlinkStreamHeartbeat8get_sizeEv)
 *(.text._ZN6matrix6MatrixIfLj3ELj1EEdVEf)
-*(.text._ZN17FlightTaskDescendC1Ev)
 *(.text._ZN26MavlinkStreamCameraTrigger8get_sizeEv)
 *(.text.iob_navail)
 *(.text._ZN12FailsafeBase25removeNonActivatedActionsEv)

platforms/common/CMakeLists.txt

@@ -47,6 +47,7 @@ add_library(px4_platform STATIC
 	i2c.cpp
 	i2c_spi_buses.cpp
 	module.cpp
+	module_params.cpp
 	px4_getopt.c
 	px4_cli.cpp
 	shutdown.cpp

platforms/common/include/px4_platform_common/module_params.h

@@ -56,19 +56,9 @@ public:
 	 * @brief Sets the parent module. This is typically not required,
 	 *         only in cases where the parent cannot be set via constructor.
 	 */
-	void setParent(ModuleParams *parent)
-	{
-		if (parent) {
-			parent->_children.add(this);
-		}
+	void setParent(ModuleParams *parent);
 
-		_parent = parent;
-	}
-
-	virtual ~ModuleParams()
-	{
-		if (_parent) { _parent->_children.remove(this); }
-	}
+	virtual ~ModuleParams();
 
 	// Disallow copy construction and move assignment.
 	ModuleParams(const ModuleParams &) = delete;

platforms/common/module_params.cpp

@@ -0,0 +1,48 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2026 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#include <px4_platform_common/module_params.h>
+
+void ModuleParams::setParent(ModuleParams *parent)
+{
+	if (parent) {
+		parent->_children.add(this);
+	}
+
+	_parent = parent;
+}
+
+ModuleParams::~ModuleParams()
+{
+	if (_parent) { _parent->_children.remove(this); }
+}

src/modules/commander/HealthAndArmingChecks/CMakeLists.txt

@@ -83,7 +83,7 @@ px4_add_library(health_and_arming_checks ${health_and_arming_checks_srcs})
 
 set_property(GLOBAL APPEND PROPERTY PX4_MODULE_CONFIG_FILES ${CMAKE_CURRENT_SOURCE_DIR}/esc_check_params.yaml)
 add_dependencies(health_and_arming_checks mode_util)
-target_link_libraries(health_and_arming_checks PRIVATE geo hysteresis)
+target_link_libraries(health_and_arming_checks PRIVATE geo hysteresis px4_platform)
 
 px4_add_functional_gtest(SRC HealthAndArmingChecksTest.cpp
 	LINKLIBS health_and_arming_checks mode_util

src/modules/commander/failsafe/CMakeLists.txt

@@ -53,6 +53,7 @@ add_executable(failsafe_test EXCLUDE_FROM_ALL
 	emscripten.cpp
 	failsafe.cpp
 	framework.cpp
+	${PX4_SOURCE_DIR}/platforms/common/module_params.cpp
 	)
 set_property(TARGET failsafe_test PROPERTY UNITY_BUILD ON) # avoids some method calls to e.g. param_name or param_type
 set_property(TARGET failsafe_test PROPERTY LINK_DEPENDS ${html_output_file})