I'm fiddling with an Arduino project where I've got these structs in my main file:

```
struct gpsCoord_t {
  long latitude;
  long longitude; 
};

struct track_t {
  char code[4];
  gpsCoord_t bounds[4];
  gpsCoord_t points[4];
};

```

Next to that I've got a function to dump variables of this type to the serial bus in that same file:

```
void dumpTrack(track_t track) {
  Serial.print("\nTrack: ");
  Serial.print(track.code);
  Serial.print("\nTrack bounds: ");
  Serial.print("\n- 1 lat: ");
  Serial.print(track.bounds[0].latitude);
  Serial.print("\n- 1 lon: ");
  Serial.print(track.bounds[0].longitude);
}

```

The compiler produces 2 errors without line numbers from which I believe the first one is caused by the second one:

```
error: variable or field 'dumpTrack' declared void
error: 'track_t' was not declared in this scope

```

EDIT here's the complete file:

```
#include <Wire.h> //I2C library
#include <I2C_eeprom.h>
#include <SoftwareSerial.h>
#include <TinyGPS.h>

I2C_eeprom ee(0x50);

const int baseTrackAddress = 3;
const int trackSize = 68;
const int maxTracks = 480;

int powerOnLED = 2;
int gpsFixLED = 3;
int trackFoundLED = 4;
int errorLED = 6;
int gpsSensor = 7;

TinyGPS gps;
SoftwareSerial nss(gpsSensor, 255);

int calcTrackAddress(int trackId) {
  return (trackId*trackSize) + baseTrackAddress;
}

struct gpsCoord_t {
  long latitude;
  long longitude; 
};

struct track_t {
  char code[4];
  gpsCoord_t bounds[4];
  gpsCoord_t points[4];
};

track_t tracks[maxTracks];

void setup() 
{
  Serial.begin(115200);
  Serial.flush();
  Serial.print("Demo I2C eeprom library ");
  Serial.print(I2C_EEPROM_VERSION);
  Serial.println("\n");

  strcpy(tracks[0].code, "X11");
  tracks[0].bounds[0].latitude = 0;
  tracks[0].bounds[0].longitude = 0;

  tracks[0].points[0].latitude = 0;
  tracks[0].points[0].longitude = 0;

  ee.writeBlock(3, (uint8_t*)&tracks[0], trackSize);
}

void loop() 
{
  Serial.println("\nTEST: 64 byte page boundary writeBlock");
  dumpEEPROM(0, 255);
  while(1);
}

void dumpTrack(track_t track) {
  Serial.print("\nTrack: ");
  Serial.print(track.code);
  Serial.print("\nTrack bounds: ");
  Serial.print("\n- 1 lat: ");
  Serial.print(track.bounds[0].latitude);
  Serial.print("\n- 1 lon: ");
  Serial.print(track.bounds[0].longitude);
}

void readTrack(int trackId) {
  track_t track;
  ee.readBlock(60, (uint8_t*)&track, 10);
}

void readTracks() {

}

void dumpEEPROM(unsigned int addr, unsigned int length)
{
  // block to 10
  addr = addr / 10 * 10;
  length = (length + 9)/10 * 10;

  byte b = ee.readByte(addr); 
  for (int i = 0; i < length; i++) 
  {
    if (addr % 10 == 0)
    {
      Serial.println();
      Serial.print(addr);
      Serial.print(":\t");
    }
    Serial.print(b);
    b = ee.readByte(++addr); 
    Serial.print("  ");
  }
  Serial.println();
}

void ProcessCommand(char* command) {
  //switch(*command==) 
}

char* ReadSerialCommand() {
  int i=0;
  char commandbuffer[100];

  if(Serial.available()){
     delay(100);
     while( Serial.available() && i< 99) {
        commandbuffer[i++] = Serial.read();
     }
     commandbuffer[i++]='\0';
  }

  if(i>0)
    return (char*)commandbuffer; 
  else
    return 0L;
}

```

When I put the entire dumpTrack function in comment, the errors go away. I've checked a couple of times for a typo but failed to find any.