NOTE: this is only applicable for ArduinoJson strictly older to 5.11.1

This may happen if you’re targeting a platform where doubles have only 32-bits.

Usually ArduinoJson can detect this, but when it doesn’t you may have the following errors:

warning: floating constant exceeds range of 'double' [-Woverflow]
warning: floating constant truncated to zero [-Woverflow]

or

Error[Pe030]: floating constant is out of range

The solution is to define ARDUINOJSON_DOUBLE_IS_64BITS to 0:

#define ARDUINOJSON_DOUBLE_IS_64BITS 0
#include <ArduinoJson.h>