netutils/paho_mqtt: configure embedded runtime mode

Expose the upstream HIGH_PERFORMANCE mode through
CONFIG_LIB_MQTT5_HIGH_PERFORMANCE and enable it by default. This keeps
normal embedded builds lightweight while allowing developers to restore
Paho heap and call-stack diagnostics when investigating library issues.

Signed-off-by: raiden00pl <raiden00@railab.me>
Assisted-by: OpenAI Codex:gpt-5

netutils/paho_mqtt/CMakeLists.txt

@@ -117,6 +117,11 @@ if(CONFIG_LIB_MQTT5)
 
   target_compile_options(mqtt5 PRIVATE ${MQTT5_FLAGS})
 
+  if(CONFIG_LIB_MQTT5_HIGH_PERFORMANCE)
+    target_compile_definitions(mqtt5 PRIVATE HIGH_PERFORMANCE=1)
+    target_compile_options(mqtt5 PRIVATE -Wno-unused-but-set-variable)
+  endif()
+
   if(CONFIG_UTILS_MQTT5)
 
     set(MQTT_PUB_FLAGS

netutils/paho_mqtt/Kconfig

@@ -16,6 +16,15 @@ config LIB_MQTT5_THREAD_STACKSIZE
 	---help---
 		Stack size used by threads created by the Paho MQTT library.
 
+config LIB_MQTT5_HIGH_PERFORMANCE
+	bool "Enable Paho high-performance mode"
+	default y
+	depends on LIB_MQTT5
+	---help---
+		Disable Paho heap-allocation tracking and function call-stack
+		tracing to reduce runtime and memory overhead. Disable this option
+		when debugging the Paho MQTT library.
+
 config UTILS_MQTT5
 	tristate "Enable mqtt5 tool"
 	depends on LIB_MQTT5

netutils/paho_mqtt/Makefile

@@ -38,6 +38,11 @@ CFLAGS += $(INCDIR_PREFIX)$(SRCDIR)
 
 ifeq ($(CONFIG_LIB_MQTT5), y)
 
+ifeq ($(CONFIG_LIB_MQTT5_HIGH_PERFORMANCE),y)
+CFLAGS += -DHIGH_PERFORMANCE=1
+CFLAGS += -Wno-unused-but-set-variable
+endif
+
 # Check if paho_mqtt directory exists, if not download and extract
 ifeq ($(wildcard $(PAHO_MQTT_UNPACK)/src),)
 $(PAHO_MQTT_ZIP):