Output turns read after 'Linking everything together...'

Development Tools IDE 2.x
1

Hi. I have been working on a sketch with an Arduino NANO 33 IoT without problem. Now I am seeing in the Output window that the text turns red on the second line after 'Linking everything together...'. Everything compiles correctly and downloads to the board and runs correctly but all the following text is red as if there is a problem. I'm thinking something is out of sync but I'm faily new to this and not sure how to proceed. I've included the code but I don't think that is the problem, as it has been running ok before.

#include <WiFiNINA.h>
#include <WiFiUdp.h>
#include <NTPClient.h>
#include <TimeLib.h>
#include <Timezone.h>

#define SSID "mySSID"
#define PASS "**********"

unsigned long lastupdate = 0UL;
time_t uk_time, utc;
int syncInterval = 300;
int syncCount;

// Define NTP Client to get time
WiFiUDP udpSocket;
NTPClient ntpClient(udpSocket, "pool.ntp.org", 0); //connect to NTP server - UTC Zone

// Create Timezone rule for United Kingdom (London, Belfast)
TimeChangeRule BST = {"BST", Last, Sun, Mar, 1, 60};        // British Summer Time
TimeChangeRule GMT = {"GMT", Last, Sun, Oct, 2, 0};         // Standard Time
Timezone UK(BST, GMT);

void setup()
{
  Serial.begin(9600);
  WiFi.begin(SSID, PASS);

  Serial.print("Connecting to ");
  Serial.print(SSID);

  while (WiFi.status() != WL_CONNECTED)
  {
    Serial.print(".");
    delay(250);
  }
    Serial.println(" Done!");

    
  ntpClient.begin(); // start ntp client
  ntpClient.update(); // get time from ntp server
  unsigned long epoch = ntpClient.getEpochTime();
  setTime(epoch); //set local clock to ntp time
  
  // Check sync stautus
  if (timeStatus() == timeNotSet) {
    // Clock is uninitialized
    Serial.println("Warning: System time is not set!");
  }
  else if (timeStatus() == timeNeedsSync) {
     // Clock is set, but the sync has failed
    Serial.println("Warning: Time not synced!");
  }
  else if (timeStatus() == timeSet) {
     // Clock is set
    Serial.println("Time is in sync");
  }
}


void loop()
{
  unsigned long currentMillis = millis();
  

  if(currentMillis - lastupdate > 1000)
  {
    syncCount ++;
    if(syncCount > syncInterval){
      syncCount = 0;
      ntpClient.update(); // get time from ntp server
      unsigned long epoch = ntpClient.getEpochTime();
      setTime(epoch); //set local clock to ntp time
      Serial.println(" Sync completed");
    }
    
    utc = now();
    uk_time = UK.toLocal(utc);
    
    Serial.print("   UTC:  ");
    Serial.print(ntpClient.getFormattedTime());
    Serial.print("    UK Time:  ");
    Serial.print(hour(uk_time));
    Serial.print(":");
    Serial.print(minute(uk_time));
    Serial.print(":");
    Serial.print(second(uk_time));
    Serial.print("    ");
    Serial.println(syncCount);
    
    lastupdate = currentMillis;
  }
}

Here is the Output from a Verify. Compile is the same but longer so I went with this one. I have marked where it turns red:-

FQBN: arduino:samd:nano_33_iot
Using board 'nano_33_iot' from platform in folder: C:\Users\daveg\AppData\Local\Arduino15\packages\arduino\hardware\samd\1.8.14
Using core 'arduino' from platform in folder: C:\Users\daveg\AppData\Local\Arduino15\packages\arduino\hardware\samd\1.8.14

Detecting libraries used...
Using cached library dependencies for file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\sketch\NTP_Clock.ino.cpp.merged
Alternatives for WiFiNINA.h: [WiFiNINA@2.1.1]
ResolveLibrary(WiFiNINA.h)
-> candidates: [WiFiNINA@2.1.1]
Alternatives for NTPClient.h: [NTPClient@3.2.1]
ResolveLibrary(NTPClient.h)
-> candidates: [NTPClient@3.2.1]
Alternatives for TimeLib.h: [Time@1.6.1]
ResolveLibrary(TimeLib.h)
-> candidates: [Time@1.6.1]
Alternatives for Timezone.h: [Timezone@1.3.0]
ResolveLibrary(Timezone.h)
-> candidates: [Timezone@1.3.0]
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\WiFi.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\WiFiClient.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\WiFiPreferences.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\WiFiSSLClient.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\WiFiServer.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\WiFiStorage.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\WiFiUdp.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\utility\WiFiSocketBuffer.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\utility\nano_rp2040_support.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\utility\server_drv.cpp
Alternatives for Arduino_SpiNINA.h: [Arduino_SpiNINA@0.0.2]
ResolveLibrary(Arduino_SpiNINA.h)
-> candidates: [Arduino_SpiNINA@0.0.2]
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA\src\utility\wifi_drv.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\NTPClient\NTPClient.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\Time\DateStrings.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\Time\Time.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\Timezone\src\Timezone.cpp
Using cached library dependencies for file: z:\Dave\Tech Stuff\Arduino Sketches\libraries\Arduino_SpiNINA\src\spi_drv.cpp
Alternatives for SPI.h: [SPI@1.0]
ResolveLibrary(SPI.h)
-> candidates: [SPI@1.0]
Using cached library dependencies for file: C:\Users\daveg\AppData\Local\Arduino15\packages\arduino\hardware\samd\1.8.14\libraries\SPI\SPI.cpp
Generating function prototypes...
Using cached sketch with function prototypes.
Compiling sketch...
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\sketch\NTP_Clock.ino.cpp.o
Compiling libraries...
Compiling library "WiFiNINA"
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\utility\nano_rp2040_support.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiSSLClient.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiStorage.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFi.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\utility\WiFiSocketBuffer.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\utility\server_drv.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiServer.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiPreferences.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\utility\wifi_drv.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiUdp.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiClient.cpp.o
Compiling library "NTPClient"
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\NTPClient\NTPClient.cpp.o
Compiling library "Time"
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\Time\Time.cpp.o
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\Time\DateStrings.cpp.o
Compiling library "Timezone"
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\Timezone\Timezone.cpp.o
Compiling library "Arduino_SpiNINA"
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\Arduino_SpiNINA\spi_drv.cpp.o
Compiling library "SPI"
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\SPI\SPI.cpp.o
Compiling core...
Using previously compiled file: C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\core\variant.cpp.o
Using precompiled core: C:\Users\daveg\AppData\Local\arduino\cores\arduino_samd_nano_33_iot_05feb1e49b17b38be042a06a5c645a27\core.a
Linking everything together...
"C:\Users\daveg\AppData\Local\Arduino15\packages\arduino\tools\arm-none-eabi-gcc\7-2017q4/bin/arm-none-eabi-g++" "-LC:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79" -Os -Wl,--gc-sections -save-temps "-TC:\Users\daveg\AppData\Local\Arduino15\packages\arduino\hardware\samd\1.8.14\variants\nano_33_iot/linker_scripts/gcc/flash_with_bootloader.ld" "-Wl,-Map,C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79/NTP_Clock.ino.map" --specs=nano.specs --specs=nosys.specs -mcpu=cortex-m0plus -mthumb -Wl,--cref -Wl,--check-sections -Wl,--gc-sections -Wl,--unresolved-symbols=report-all -Wl,--warn-common -Wl,--warn-section-align -o "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79/NTP_Clock.ino.elf" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\sketch\NTP_Clock.ino.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFi.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiClient.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiPreferences.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiSSLClient.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiServer.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiStorage.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\WiFiUdp.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\utility\WiFiSocketBuffer.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\utility\nano_rp2040_support.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\utility\server_drv.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\WiFiNINA\utility\wifi_drv.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\NTPClient\NTPClient.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\Time\DateStrings.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\Time\Time.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\Timezone\Timezone.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\Arduino_SpiNINA\spi_drv.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\libraries\SPI\SPI.cpp.o" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79\core\variant.cpp.o" -Wl,--start-group "-LC:\Users\daveg\AppData\Local\Arduino15\packages\arduino\tools\CMSIS\4.5.0/CMSIS/Lib/GCC/" -larm_cortexM0l_math -lm "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79/..\..\cores\arduino_samd_nano_33_iot_05feb1e49b17b38be042a06a5c645a27\core.a" -Wl,--end-group

GOES RED FROM HERE>>>>
c"C:\Users\daveg\AppData\Local\Arduino15\packages\arduino\tools\arm-none-eabi-gcc\7-2017q4/bin/arm-none-eabi-objcopy" -O binary "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79/NTP_Clock.ino.elf" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79/NTP_Clock.ino.bin"
:/users/daveg/appdata/local/arduino15/packages/arduino/tools/arm-none-eabi-gcc/7-2017q4/bin/../lib/gcc/arm-none-eabi/7.2.1/../../../../arm-none-eabi/bin/ld.exe: warning: changing start of section .bss by 4 bytes
c:/users/daveg/appdata/local/arduino15/packages/arduino/tools/arm-none-eabi-gcc/7-2017q4/bin/../lib/gcc/arm-none-eabi/7.2.1/../../../../arm-none-eabi/bin/ld.exe: warning: changing start of section .bss by 4 bytes
c:/users/daveg/appdata/local/arduino15/packages/arduino/tools/arm-none-eabi-gcc/7-2017q4/bin/../lib/gcc/arm-none-eabi/7.2.1/../../../../arm-none-eabi/bin/ld.exe: warning: changing start of section .bss by 4 bytes
c:/users/daveg/appdata/local/arduino15/packages/arduino/tools/arm-none-eabi-gcc/7-2017q4/bin/../lib/gcc/arm-none-eabi/7.2.1/../../../../arm-none-eabi/bin/ld.exe: warning: changing start of section .bss by 4 bytes
c:/users/daveg/appdata/local/arduino15/packages/arduino/tools/arm-none-eabi-gcc/7-2017q4/bin/../lib/gcc/arm-none-eabi/7.2.1/../../../../arm-none-eabi/bin/ld.exe: warning: changing start of section .bss by 4 bytes
"C:\Users\daveg\AppData\Local\Arduino15\packages\arduino\tools\arm-none-eabi-gcc\7-2017q4/bin/arm-none-eabi-objcopy" -O ihex -R .eeprom "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79/NTP_Clock.ino.elf" "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79/NTP_Clock.ino.hex"
Using library WiFiNINA at version 2.1.1 in folder: Z:\Dave\Tech Stuff\Arduino Sketches\libraries\WiFiNINA
Using library NTPClient at version 3.2.1 in folder: Z:\Dave\Tech Stuff\Arduino Sketches\libraries\NTPClient
Using library Time at version 1.6.1 in folder: Z:\Dave\Tech Stuff\Arduino Sketches\libraries\Time
Using library Timezone at version 1.3.0 in folder: Z:\Dave\Tech Stuff\Arduino Sketches\libraries\Timezone
Using library Arduino_SpiNINA at version 0.0.2 in folder: Z:\Dave\Tech Stuff\Arduino Sketches\libraries\Arduino_SpiNINA
Using library SPI at version 1.0 in folder: C:\Users\daveg\AppData\Local\Arduino15\packages\arduino\hardware\samd\1.8.14\libraries\SPI
"C:\Users\daveg\AppData\Local\Arduino15\packages\arduino\tools\arm-none-eabi-gcc\7-2017q4/bin/arm-none-eabi-size" -A "C:\Users\daveg\AppData\Local\arduino\sketches\32654A0F46CDF67D3FE046A33041FA79/NTP_Clock.ino.elf"
Sketch uses 21892 bytes (8%) of program storage space. Maximum is 262144 bytes.
Global variables use 4136 bytes (12%) of dynamic memory, leaving 28632 bytes for local variables. Maximum is 32768 bytes.
2

Please edit your post and put the compiler output in code tags to make it easier to read and manage

3

Before trying to explain the warning itself, I'd first establish what changed. Did the sketch change, or did the build environment (IDE, SAMD core, toolchain or libraries) change? That would significantly narrow down the search space.

4

Warnings follow, not necessarily a problem e.g.:

gcc/7-2017q4/bin/../lib/gcc/arm-none-eabi/7.2.1/../../../../arm-none-eabi/bin/ld.exe: warning: changing start of section .bss by 4 bytes

Does the program run without noticeable problems or errors?

5

Yes, it downloads and runs without any errors.

6

I don't think I had made any changes to the code when the problem arose.

7

Then don't worry about it. However if you want to follow this or similar issues up, a web search for a suitable portion of the error message text often turns up helpful comments or actionable suggestions.

For example:

This warning indicates that the linker is adjusting the start of the .bss section by 4 bytes to align memory properly, which is not an error and can be safely ignored if your project is functioning correctly. It typically occurs due to how the compiled code aligns with the microcontroller's memory architecture.

forum.arduino.cc forum.seeedstudio.com

8

Thank you @anon94801460 . That does seem to be the case as it all runs ok.