Redeclared as different kind of symbol - ESP32 dev board

Projects Programming
1

It will not compile:

volatile float y1 = 0;
volatile float y2 = 0;

void setup() {}

void loop() {}

I am using an ESP32 development board. Is there a list somewhere of reserved words?*

706×574 23.2 KB

I added this library:

  1. File → Preferences, paste in Additional Boards Manager URLs:
    https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json

  2. Tools → Board: “[…]” → Boards Manager, search for esp32 and install.

*If so, it might be here: GitHub - espressif/arduino-esp32: Arduino core for the ESP32
(I don't know how to navigate or where it would be found.)

2

adamelli:
(I don't know how to navigate or where it would be found.)

If you look at the full error message. It tells you where this specific declaration is:

sketch_nov18a:1:16: error: 'volatile float y1' redeclared as different kind of symbol
 volatile float y1 = 0;
                ^
In file included from C:\Users\per\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.4\cores\esp32/esp32-hal.h:34:0,
                 from C:\Users\per\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.4\cores\esp32/Arduino.h:35,
                 from C:\Users\per\AppData\Local\Temp\arduino_build_837701\sketch\sketch_nov18a.ino.cpp:1:
C:\Users\per\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.4/tools/sdk/include/newlib/math.h:475:15: note: previous declaration 'double y1(double)'
 extern double y1 _PARAMS((double));
               ^
exit status 1
'volatile float y1' redeclared as different kind of symbol

You can see that on my computer it's at line 475 of the file C:\Users\per\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.4/tools/sdk/include/newlib/math.h

The file will be in a different location on your computer.

3

Thanks!

(I realize now, I get tunnel vision looking at those error messages--usually don't understand most of it.)