error: 'const void*' is not a pointer-to-object type

[tbillion]

Description
/home/t/Arduino/libraries/ArduinoJson/src/ArduinoJson/Polyfills/pgmspace_generic.hpp: In instantiation of 'typename ArduinoJson6194_F1::enable_if<ArduinoJson6194_F1::is_pointer::value, T>::type ArduinoJson6194_F1::pgm_read(const void*) [with T = const arduino::__FlashStringHelper*; typename ArduinoJson6194_F1::enable_if<ArduinoJson6194_F1::is_pointer::value, T>::type = const arduino::__FlashStringHelper*]':
/home/t/Arduino/libraries/ArduinoJson/src/ArduinoJson/Deserialization/DeserializationError.hpp:85:12: required from here
/home/t/Arduino/libraries/RF24/RF24_config.h:206:38: error: 'const void*' is not a pointer-to-object type
206 | #define pgm_read_ptr(p) (*(p))
| ~^~~~~
exit status 1

Troubleshooter's report

1. The issue happens at compile time
2. The error is not in the list

Environment

• Microcontroller: pico
• Core/Framework: ear philhower most recent
• IDE: 1.8.16

Reproduction code

just adding the library throws the error , no actual code to perform actions has been added

Remarks
nope would just like it to work.

edit

it has something to do with the order in which it is added to the project ...
if i add them like this it will not compile.

#include <FanController.h>
#include <WS2812FX.h>
#include "namedColors256.h"
#include "RF24.h"
#include "RF24Network.h"
#include "RF24Mesh.h"
#include <SPI.h>
#include <EEPROM.h>
#include <LittleFS.h>
#include <ArduinoJson.h>

if i add them like this it will compile.

#include <ArduinoJson.h>
#include <FanController.h>
#include <WS2812FX.h>
#include "namedColors256.h"
#include "RF24.h"
#include "RF24Network.h"
#include "RF24Mesh.h"
#include <SPI.h>
#include <EEPROM.h>
#include <LittleFS.h>

[bblanchon]

Hi @tbillion,

'const void*' is not a pointer-to-object type

This error is in the list. Please look again.

Best regards,
Benoit

[bblanchon]

Related to arduino/ArduinoCore-API#118.
Duplicate of #1442, #1519, #1536, #1591, and #1676.

[bblanchon]

In this case, it seems that the bug doesn't come from the core but from the RF24 library.
I'll open a PR.

[2bndy5]

@tbillion It would help to know the version of RF24 that you are using, so I can reproduce this.

[bblanchon]

@2bndy5, here is a complete repro:

#include <RF24.h>
#include <ArduinoJson.h>

void setup() {}
void loop() {}

With RF24 v1.4.5, these four lines produce an error on some Arduino cores:

Core	Status
Adafruit SAMD	OK
Arduino AVR	OK
Arduino Mbed	Error
Arduino megaAVR	OK
Arduino SAMD	OK
ESP32	OK
ESP8266	OK
Raspberry Pi RP2040	Error
STM32	OK
STM32F1	OK
STM32F4	Error
Teensy 4	OK
Teensy 3	OK
Infineon XMC	Error

[2bndy5]

Thanks, that helps narrow down the cores, but the error in the OP doesn't seem to align with v1.4.5. I have a hunch at which line is the problem, but I just wanted to be sure.

[tbillion]

1.4.3

If it is not a breaking change I will upgrade and see if it persists .

[2bndy5]

Avoid v1.4.4 because there is a known bug which was fixed in v1.4.5 (the latest). However, updating the lib won't likely fix this problem. I just wanted to know what version you were using so I could find the exact line that was causing the problem. Thank you for the response.

[2bndy5]

I will let you know when the fix for this has been released (likely going to be v1.4.6) for the Arduino Library Manager... It should be soon, but I wanted to go through and fix the other pgm_read_* macros and add printf_P support to the arduino-pico core (+ ESP32/8266 cores).

[2bndy5]

I just released v1.4.6 which includes the fix for this. Please wait at least 24 hours for the release to get picked up by the Arduino Lib Manager, then update and enjoy...