ArduinoJson: F.A.Q


There is currently a bug in the Arduino Core for ESP32 causing the following error:

error: redefinition of 'struct ArduinoJson::Internals::StringFuncs<const char*>'

The solution is to disable PROGMEM support in ArduinoJson. To do that, just add the following line at the top of your program:


Then, you may have the following linker error:

undefined reference to__cxa_guard_release'

To solve this, you need to add -fno-threadsafe-statics in platform.txt.

See issue #407

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