Marlin 2.0.7.2 failed to compile with the feature of "controller fan" for arduino DUE

[hkckko]

Marlin 2.0.7.2
Arduino IDE 1.8.13 running under ubuntu OS
Target: Arduino Due (Programming Port)
When enable the "USE_CONTROLLER FAN" in "Configuration_adv.h"

#define USE_CONTROLLER_FAN
#if ENABLED(USE_CONTROLLER_FAN)
#define CONTROLLER_FAN_PIN 11
//#define CONTROLLER_FAN_USE_Z_ONLY // With this option only the Z axis is considered
//#define CONTROLLER_FAN_IGNORE_Z // Ignore Z stepper. Useful when stepper timeout is disabled.
#define CONTROLLERFAN_SPEED_MIN 0 // (0-255) Minimum speed. (If set below this value the fan is turned off.)
#define CONTROLLERFAN_SPEED_ACTIVE 255 // (0-255) Active speed, used when any motor is enabled
#define CONTROLLERFAN_SPEED_IDLE 0 // (0-255) Idle speed, used when motors are disabled
#define CONTROLLERFAN_IDLE_TIME 10 // (seconds) Extra time to keep the fan running after disabling motors
//#define CONTROLLER_FAN_EDITABLE // Enable M710 configurable settings
#if ENABLED(CONTROLLER_FAN_EDITABLE)
#define CONTROLLER_FAN_MENU // Enable the Controller Fan submenu
#endif
#endif_

The following compiling errors were observed:

In file included from sketch/src/MarlinCore.cpp:209:0:
sketch/src/feature/controllerfan.h:61:67: error: non-constant in-class initialization invalid for static member 'ControllerFan::settings'
static const controllerFan_settings_t constexpr &settings = controllerFan_defaults;
^
sketch/src/feature/controllerfan.h:61:67: error: (an out of class initialization is required)
sketch/src/feature/controllerfan.h:61:67: error: 'ControllerFan::settings' cannot be initialized by a non-constant expression when being declared
exit status 1
Error compiling for board Arduino Due (Programming Port).

[boelle]

does this also happen if you use vscode+platform.io ?
(this is the prefered choice as arduino ide is filled with bugs that only arduino people can fix - and they dont)

i use a re-arm and not the due but i dont have any compile errors

[ellensp]

What DUE based motherboard, there are 28 possibilities...

[ellensp]

I guessed a motherboard, added a CONTROLLER_FAN_PIN and can replicate the error in arduinio ide.
PlatformIO does not error. and takes about 1/3 or the time to compile.

[ellensp]

Enabling CONTROLLER_FAN_EDITABLE bypasses the the issue

[ellensp]

Looks like the following line in Marlin/src/feature/controllerfan.h really shouldn't have the &.
static const controllerFan_settings_t constexpr &settings = controllerFan_defaults;

[hkckko]

Thank your for boelle's and ellensp's advice.

It is success to compile with PlatformIO under windows environment.
I think the problem shall be caused by the Arduino IDE.

[shitcreek]

The & operator seems to cause issue for STM32 in general. Such as:
#19431 (comment)

[sjasonsmith]

A pull request is posted to fix this.

[sjasonsmith]

My changes have been merged. Closing as presumed fixed.

[github-actions]

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