# ESP32 compilation problems **URL:** \ **Category:** Programming\ **Created:** [April 17, 2025, 2:43pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305 "2025-04-17T14:43:27Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![evanmars](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/evanmars/32/217678_2.png) [@evanmars](https://forum.arduino.cc/u/evanmars)\ **Post date:** [April 17, 2025, 2:43pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/1 "2025-04-17T14:43:27Z")
Selected board: ESP32 Dev Module IDE: 2.3.6 Am I missing something? I can't even compile an empty sketch for ESP32. Selected Uno and deleted the include and it works fine. ```cpp #include void setup() { // put your setup code here, to run once: } void loop() { // put your main code here, to run repeatedly: } ``` ```arduino C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\Arduino15\packages\esp32\tools\esp32-arduino-libs\idf-release_v5.4-2f7dcd86-v1\esp32/lib\libesp_system.a(panic_handler.c.obj):(.literal.panic_handler+0x2c): undefined reference to `__wrap_esp_panic_handler' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\Arduino15\packages\esp32\tools\esp32-arduino-libs\idf-release_v5.4-2f7dcd86-v1\esp32/lib\libesp_system.a(panic_handler.c.obj): in function `frame_to_panic_info': /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/esp_system/port/panic_handler.c:113:(.text.panic_handler+0x13b): undefined reference to `__wrap_esp_panic_handler' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\Arduino15\packages\esp32\tools\esp32-arduino-libs\idf-release_v5.4-2f7dcd86-v1\esp32/lib\libfreertos.a(app_startup.c.obj):(.literal.main_task+0x14): undefined reference to `app_main' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\Arduino15\packages\esp32\tools\esp32-arduino-libs\idf-release_v5.4-2f7dcd86-v1\esp32/lib\libfreertos.a(app_startup.c.obj): in function `main_task': /home/runner/work/esp32-arduino-lib-builder/esp32-arduino-lib-builder/esp-idf/components/freertos/app_startup.c:199:(.text.main_task+0x60): undefined reference to `app_main' collect2.exe: error: ld returned 1 exit status exit status 1 Compilation error: exit status 1 ``` ---
**Author:** ![UKHeliBob](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/ukhelibob/32/215663_2.png) [@UKHeliBob](https://forum.arduino.cc/u/UKHeliBob)\ **Post date:** [April 17, 2025, 2:47pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/2 "2025-04-17T14:47:33Z")
It looks like the ESP32 board installation has problems. Uninstall it and install it again ---
**Author:** ![evanmars](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/evanmars/32/217678_2.png) [@evanmars](https://forum.arduino.cc/u/evanmars)\ **Post date:** [April 17, 2025, 2:50pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/3 "2025-04-17T14:50:57Z")
That was my first thought. Since this is a new Arduino install, I uninstalled everything Arduino and reinstalled. Same problem. ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 17, 2025, 2:51pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/4 "2025-04-17T14:51:59Z")
What EXACTLY did you install? Also, show your preferences for additional board URLS. ---
**Author:** ![evanmars](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/evanmars/32/217678_2.png) [@evanmars](https://forum.arduino.cc/u/evanmars)\ **Post date:** [April 17, 2025, 2:54pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/5 "2025-04-17T14:54:11Z")
esp32 by Espressif Systems v3.2.0 Additional boards manager URLs: is blank ![image](https://europe1.discourse-cdn.com/arduino/original/4X/2/2/0/2202312758a309de2f08384d3e863ebc3ed990d9.png) ---
**Author:** ![adminakm2009](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/adminakm2009/32/1131580_2.png) [@adminakm2009](https://forum.arduino.cc/u/adminakm2009)\ **Post date:** [April 17, 2025, 2:56pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/6 "2025-04-17T14:56:12Z")
The issue you're encountering seems to be related to the `app_main` function, which is part of the ESP32's IDF (Espressif IoT Development Framework) but not a part of the standard Arduino framework for the ESP32. ### Why this is happening: - In the Arduino IDE, you don’t need to define an `app_main` function because the Arduino framework handles the setup and loop functions for you. - However, when using the ESP32 IDF or the ESP32 Arduino core, the `app_main` function is required for lower-level system tasks and the FreeRTOS kernel, which is why you're seeing the errors about `app_main` and `__wrap_esp_panic_handler`. ### How to Fix: 1. **Make sure you're using the right board selection** : In the Arduino IDE, make sure you’ve selected the correct board (ESP32, not Uno). You can do this from the **Tools \> Board** menu. 2. **Check for proper libraries and core installation** : Ensure that the ESP32 board support is installed correctly. You can do this through the **Boards Manager** in the Arduino IDE (under **Tools \> Board \> Board Manager** ). 3. **Verify that you have no residual or incorrect settings** : If you’ve previously selected an Arduino Uno or other board, and then switched to ESP32, sometimes old settings can cause issues. Try going to **Tools \> Board \> ESP32** again, and double-check the settings. 4. **Empty Sketch for ESP32** : To test if everything works without issues, use this minimal code (this should work for ESP32): cpp CopyEdit ```arduino void setup() { Serial.begin(115200); // Add setup code here } void loop() { // Add loop code here } ``` 1. **Remove `#include `** : It’s unnecessary to include `Arduino.h` explicitly when working with ESP32, as the framework should include it by default. However, leaving it should also not cause an issue, but try removing it if you continue to face issues. 2. **IDE Restart** : If you’ve made changes, restart the Arduino IDE to ensure all settings are properly refreshed. If you're still having trouble, let me know what board version and platform you're using, and I can help you troubleshoot further. ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 17, 2025, 2:58pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/7 "2025-04-17T14:58:27Z")
If you want to work with esp32 then you need a boards URL. After you enyter this, restart the IDE then use the boards button on left and select as shown in screen grab. Here is the 'official' boards URL. You are most likely using Arduino esp32, that is not what you want for Espressif boards. [https://espressif.github.io/arduino-esp32/package\_esp32\_index.json](https://espressif.github.io/arduino-esp32/package_esp32_index.json) ![Screenshot 2025-04-17 at 10.57.00](https://europe1.discourse-cdn.com/arduino/original/4X/c/f/c/cfce8fc42624ecb64537114055b819e3cf10e3cb.png) ---
**Author:** ![evanmars](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/evanmars/32/217678_2.png) [@evanmars](https://forum.arduino.cc/u/evanmars)\ **Post date:** [April 17, 2025, 3:00pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/8 "2025-04-17T15:00:38Z")
Third time is the charm? I just uninstalled and reinstall esp32 and my blank sketch compiled. I am now trying to compile a larger sketch. Will update when it completes (or fails). ---
**Author:** ![evanmars](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/evanmars/32/217678_2.png) [@evanmars](https://forum.arduino.cc/u/evanmars)\ **Post date:** [April 17, 2025, 3:05pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/9 "2025-04-17T15:05:42Z")
I reinstalled esp32 3.2.0 (as I stated I had installed in post #5) and my empty sketch compiled. Still no URL listed in Additional boards manager. ![image](https://europe1.discourse-cdn.com/arduino/original/4X/3/5/9/3596d4c859cce42d0d9e2ddf9f44a5dc7217331a.png) ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 17, 2025, 3:21pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/10 "2025-04-17T15:21:47Z")
It looks like you previously installed the espressif boards but have since removed the url from the Additional boards manager URLs. Put the URL I gave you for Espressif back in the Additional boards, then do a remove followed by an install. Now we are at square ZERO. While you do that I will reread your posts to determine what if any real error you may have. BTW, your prefs need some work, turn on verbose, also I would add Editor Quick Suggestions, warnings to Default. BTW WHAT IS \epcfs ????? ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 17, 2025, 3:25pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/11 "2025-04-17T15:25:10Z")
You can't install the ESP boards if you don;t have the additional boards URL. I have no idea what your environment is, but it isn;t stock Arduino. If you want stock Arduino, please follow the directions we give you, if you do NOT want stock Arduino IDE, then let me know so I can ignore you as I can't help. ---
**Author:** ![evanmars](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/evanmars/32/217678_2.png) [@evanmars](https://forum.arduino.cc/u/evanmars)\ **Post date:** [April 17, 2025, 5:03pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/12 "2025-04-17T17:03:20Z")
I don't know how much more stock Arduino it can be. I literally: - uninstalled Arduino - found every file with a reference to Arduino afterwards and deleted them - redownloaded the installer and ran it. It asked if I wanted just me to have access to the program or all users of the computer; I selected all (previously had selected just me). - went to the Boards manager icon on the left of the IDE, scrolled to esp32 and installed v3.0.2. I never uninstalled any URLs from the Additional boards manager. But after my **_successful_ compile** of the bare sketch (after clicking Remove for esp32 and then clicking Install again as I mentioned in post #8 and #9), I put the link you sent in it. I do not have any problems compiling the bare sketch. This was a new install of the IDE and I hadn't checked the boxes for verbose and Quick Suggestions yet, I have since. I usually have those checked, just hadn't done it for this new fresh install. So, I am thinking I may have some sort of permissions issue. I am using a work computer which I generally have Admin rights for. Haven't had any issue with Arduino on this machine before, but who knows? \\epcfs1 is a share on the server. Arduino won't let me choose where to put the Sketchbook location, so it ends up here instead of c:\users\evan.marshall\documents. I am now back at my original issue which is why I tried the bare sketch _ **which is now working** _: Trying to compile the ESP-Mail-Client example. [ESP-Mail-Client/examples/SMTP/Send\_Attachment\_File/Send\_Attachment\_File.ino at master · mobizt/ESP-Mail-Client · GitHub](https://github.com/mobizt/ESP-Mail-Client/blob/master/examples/SMTP/Send_Attachment_File/Send_Attachment_File.ino) Should I continue here, or start a new thread? ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 17, 2025, 5:22pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/13 "2025-04-17T17:22:43Z")
As far as I know, you can NOT install esp2 by Espressif NOTE NOT the Arduino esp32! UNTIL you add the esp32 boards URL to the additional boards manager. BUT I am going to back up my arduino environment and do a fresh install the same way you did to see what happens. Back in a few. ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 17, 2025, 5:28pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/14 "2025-04-17T17:28:01Z")
Here is the official Espressif install instructions. If you did NOT follow this BUT were able ti install esp32 v3.0.2 then you picked up a previous install, the current version is 3.2.0. [https://docs.espressif.com/projects/arduino-esp32/en/latest/installing.html#installing-using-arduino-ide](https://docs.espressif.com/projects/arduino-esp32/en/latest/installing.html#installing-using-arduino-ide) ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 17, 2025, 5:37pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/15 "2025-04-17T17:37:45Z")
Here is a comparison of a 100% fresh install showing onhy builtin libs, NO cores. And my normal showing 11 different board families plus builtin. Next after I selected the grayed out ESP32DEV board I was prompted to install the core. I did and that is what is shown in the last screen grab. For the best experience, follow the espressif doc's and add the additional url for esp32. I think we are done. ![Screenshot 2025-04-17 at 13.29.29](https://europe1.discourse-cdn.com/arduino/original/4X/6/c/b/6cbc928e1df9b5a39d5995eb9bd745ac90db7009.png) ![Screenshot 2025-04-17 at 13.30.09](https://europe1.discourse-cdn.com/arduino/original/4X/3/f/2/3f2d47945824f46fb05ba7634fe30b5b89326869.png) ![Screenshot 2025-04-17 at 13.30.20](https://europe1.discourse-cdn.com/arduino/original/4X/2/7/5/27532277fd66a1c52f6b0a3d809851feac7ccd11.png) ![Screenshot 2025-04-17 at 13.32.56](https://europe1.discourse-cdn.com/arduino/original/4X/f/0/2/f02b94bdbc914da1fa47cf76d26dba57e279e5b1.png) ![Screenshot 2025-04-17 at 13.35.22](https://europe1.discourse-cdn.com/arduino/original/4X/d/1/b/d1b4549c0fbcd7ddffa96d8fc6885916218147ac.png) ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 17, 2025, 5:44pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/16 "2025-04-17T17:44:11Z")
Which example in that library do you want to use. I have installed the library and I will try to compile the same sketch. ---
**Author:** ![evanmars](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/evanmars/32/217678_2.png) [@evanmars](https://forum.arduino.cc/u/evanmars)\ **Post date:** [April 17, 2025, 5:49pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/17 "2025-04-17T17:49:39Z")
Send\_Attachment\_File.ino Here is the error log I am getting. I moved the Arduino folder from \\epcfs1 to c:\users\evan.marshall\documents. ```arduino FQBN: esp32:esp32:esp32 Using board 'esp32' from platform in folder: C:\Users\evan.marshall\AppData\Local\Arduino15\packages\esp32\hardware\esp32\3.2.0 Using core 'esp32' from platform in folder: C:\Users\evan.marshall\AppData\Local\Arduino15\packages\esp32\hardware\esp32\3.2.0 ... C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ar.exe: unable to copy file 'C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\bssl\objs.a'; reason: Permission denied ... C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\bssl\objs.a(ec_all_m31.c.o):(.literal.api_mul+0x8): undefined reference to `br_ec_prime_i31' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x4): undefined reference to `br_md5_vtable' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x8): undefined reference to `br_sha1_vtable' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0xc): undefined reference to `br_sha224_vtable' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x10): undefined reference to `br_sha256_vtable' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x14): undefined reference to `br_sha384_vtable' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x18): undefined reference to `br_sha512_vtable' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x1c): undefined reference to `br_tls10_prf' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x20): undefined reference to `br_tls12_sha256_prf' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x24): undefined reference to `br_tls12_sha384_prf' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x28): undefined reference to `br_ssl_client_zero' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x2c): undefined reference to `br_ssl_engine_set_suites' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x30): undefined reference to `br_ssl_client_set_default_rsapub' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x34): undefined reference to `br_ssl_engine_set_default_rsavrfy' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x38): undefined reference to `br_ssl_engine_set_default_ecdsa' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x3c): undefined reference to `br_ssl_engine_set_default_aes_cbc' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x40): undefined reference to `br_ssl_engine_set_default_aes_gcm' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x44): undefined reference to `br_ssl_engine_set_default_aes_ccm' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x48): undefined reference to `br_ssl_engine_set_default_des_cbc' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.br_ssl_client_base_init+0x4c): undefined reference to `br_ssl_engine_set_default_chapol' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.insecure_start_chain+0x4): undefined reference to `br_sha1_init' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.insecure_start_chain+0x8): undefined reference to `br_sha256_init' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.insecure_subject_dn_append+0x0): undefined reference to `br_sha224_update' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client4peekEv+0xc): undefined reference to `br_ssl_engine_recvapp_buf' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.insecure_end_chain+0x0): undefined reference to `br_sha1_out' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.insecure_end_chain+0x4): undefined reference to `br_sha256_out' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal.insecure_append+0x0): undefined reference to `br_sha1_update' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client4readEPhj+0x0): undefined reference to `br_ssl_engine_recvapp_ack' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client9connectedEv+0xc): undefined reference to `br_ssl_engine_current_state' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client13mUpdateEngineEv+0x18): undefined reference to `br_ssl_engine_sendrec_buf' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client13mUpdateEngineEv+0x1c): undefined reference to `br_ssl_engine_sendrec_ack' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client13mUpdateEngineEv+0x20): undefined reference to `br_ssl_engine_sendapp_buf' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client13mUpdateEngineEv+0x24): undefined reference to `br_ssl_engine_sendapp_ack' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client13mUpdateEngineEv+0x28): undefined reference to `br_ssl_engine_recvrec_buf' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client13mUpdateEngineEv+0x2c): undefined reference to `br_ssl_engine_recvrec_ack' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client9availableEv+0xc): undefined reference to `br_ssl_engine_flush' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client27mInstallClientX509ValidatorEv+0x30): undefined reference to `br_x509_knownkey_init_rsa' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client27mInstallClientX509ValidatorEv+0x3c): undefined reference to `br_x509_knownkey_init_ec' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client27mInstallClientX509ValidatorEv+0x40): undefined reference to `br_x509_minimal_init' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client11mConnectSSLEPKc+0x30): undefined reference to `br_ssl_engine_set_buffers_bidi' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client11mConnectSSLEPKc+0x34): undefined reference to `br_ssl_engine_inject_entropy' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client11mConnectSSLEPKc+0x38): undefined reference to `br_ssl_client_reset' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client11mConnectSSLEPKc+0x44): undefined reference to `br_rsa_pkcs1_sign_get_default' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client11mConnectSSLEPKc+0x48): undefined reference to `br_ssl_client_set_single_rsa' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client11mConnectSSLEPKc+0x54): undefined reference to `br_ecdsa_sign_asn1_get_default' C:/Users/evan.marshall/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\evan.marshall\AppData\Local\arduino\sketches\08C85AEE9EEBB7C0B15C4D29D652BA51\libraries\ESP_Mail_Client\client\SSLClient\client\objs.a(BSSL_SSL_Client.cpp.o):(.literal._ZN15BSSL_SSL_Client11mConnectSSLEPKc+0x58): undefined reference to `br_ssl_client_set_single_ec' etc., etc. ... exit status 1 Compilation error: exit status 1 ``` ---
**Author:** ![evanmars](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/evanmars/32/217678_2.png) [@evanmars](https://forum.arduino.cc/u/evanmars)\ **Post date:** [April 17, 2025, 5:56pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/18 "2025-04-17T17:56:56Z")
Trimmed error code as it was, as they say, verbose. About 10000 characters too long. ---
**Author:** ![sonofcy](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/sonofcy/32/1283617_2.png) [@sonofcy](https://forum.arduino.cc/u/sonofcy)\ **Post date:** [April 17, 2025, 6:00pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/19 "2025-04-17T18:00:28Z")
Compiles just fine. Just add the esp32 url to additional bioards, then restart IDE, then select the esp32 by Espressif and Install (it should be 3.2.0) and you are all set. In order to build for a board, you must first add the relevenat boards URL to the prefs additional boards, then install A SINGLE family via the Boards Manager. What happens (I just learned) @ptillisch is that if you do NOT have an additional boards entry, the IDE picks up a boards file from somewhere and saves it somewhere that I never heard of before. BUT that is not correct and may be a bug. ![Screenshot 2025-04-17 at 13.54.58](https://europe1.discourse-cdn.com/arduino/original/4X/1/3/6/136cb9c430830b5c3e4bd73ec4229485f6cd95cd.png) ---
**Author:** ![evanmars](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/evanmars/32/217678_2.png) [@evanmars](https://forum.arduino.cc/u/evanmars)\ **Post date:** [April 17, 2025, 6:33pm UTC](https://forum.arduino.cc/t/esp32-compilation-problems/1374305/20 "2025-04-17T18:33:30Z")
I give up. I'm going to try my Linux machine when I get home. ![image](https://europe1.discourse-cdn.com/arduino/original/4X/8/4/2/8425fe5e47a17b901b87ae06f18c025d159ab008.png) [Next page](https://forum.arduino.cc/t/esp32-compilation-problems/1374305.md?page=2)