CODEWITHSUNDEEP
csizeof
Apez
Apez

Reputation: 1

Invalid application of 'sizeof' to incomplete type question

Im getting the error of

invalid application of 'sizeof' to incomplete type 'TProgmemRGBGradientPalette_byte* const [] {aka const unsigned char* const []}'

On line 46 https://pastebin.com/xhVEnqts.

The last line below is line 46:

#define FASTLED_ALLOW_INTERRUPTS 0
#include "FastLED.h"
#include <Arduino.h>
#include <ESP8266WiFi.h>
#include <ESP8266WiFiMulti.h>
#include <WebSocketsClient.h> //  https://github.com/kakopappa/sinric/wiki/How-to-add-dependency-libraries
#include <ArduinoJson.h> // https://github.com/kakopappa/sinric/wiki/How-to-add-dependency-libraries
#include <StreamString.h>

#define DATA_PIN    3
#define LED_TYPE    WS2812
#define COLOR_ORDER GRB
#define NUM_LEDS    30       // Change this to reflect the number of LEDs you have
#define BRIGHTNESS  128       // Set Brightness here

CRGB leds[NUM_LEDS];

#define SECONDS_PER_PALETTE 15


ESP8266WiFiMulti WiFiMulti;
WebSocketsClient webSocket;
WiFiClient client;

#define MyApiKey "xxxx" // TODO: Change to your sinric API Key. Your API Key is displayed on sinric.com dashboard
#define MySSID "xxxxx" // TODO: Change to your Wifi network SSID
#define MyWifiPassword "xxxx" // TODO: Change to your Wifi network password

#define HEARTBEAT_INTERVAL 300000 // 5 Minutes

uint64_t heartbeatTimestamp = 0;
bool isConnected = false;

void setPowerStateOnServer(String deviceId, String value);
void setTargetTemperatureOnServer(String deviceId, String value, String scale);

extern const TProgmemRGBGradientPalettePtr gGradientPalettes[];
extern const uint8_t gGradientPaletteCount;

uint8_t gCurrentPaletteNumber = 0;

CRGBPalette16 gCurrentPalette( CRGB::Black);
CRGBPalette16 gTargetPalette( gGradientPalettes[0] );

const uint8_t gGradientPaletteCount =
sizeof( gGradientPalettes) / sizeof( TProgmemRGBGradientPalettePtr );

Upvotes: 0

Views: 1652

Answers (2)

P.W
P.W

Reputation: 26800

An array type is an incomplete type if its size is not present, and sizeof cannot be applied on an incomplete type.

The following line means that the definition of gGradientPalettes is present in some other file. 

extern const TProgmemRGBGradientPalettePtr gGradientPalettes[];

The compiler is not able to find this definition and so it complains at this line: 

const uint8_t gGradientPaletteCount =
sizeof( gGradientPalettes) / sizeof( TProgmemRGBGradientPalettePtr );

Upvotes: 1

0___________
0___________

Reputation: 67713

It extern variable with unknown compile time size. If you cant find the size looking at the code compiler will not as well

Upvotes: 1

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