Platformio undefined reference to app_main

[Mark H. (kehafu)]

Hallo,

ich kriege beim Kompilieren von ...

https://github.com/joachimBurket/esp32-opencv/tree/master/esp32/examples/hello_opencv

... mit PlatformIO folgende Fehlermeldung:

[build] [ 99%] Linking CXX executable hello_opencv.elf

[build] /home/mongoq/.platformio/packages/toolchain-xtensa-esp32/bin/…/lib/gcc/xtensa-esp32-elf/8.4.0/…/…/…/…/xtensa-esp32-elf/bin/ld: esp-idf/freertos/libfreertos.a(port_common.c.obj):(.literal.main_task+0x1c): undefined reference to `app_main’

[build] /home/mongoq/.platformio/packages/toolchain-xtensa-esp32/bin/…/lib/gcc/xtensa-esp32-elf/8.4.0/…/…/…/…/xtensa-esp32-elf/bin/ld: esp-idf/freertos/libfreertos.a(port_common.c.obj): in function `main_task’:

[build] /home/mongoq/.platformio/packages/framework-espidf/components/freertos/port/port_common.c:122: undefined reference to `app_main’

[build] collect2: error: ld returned 1 exit status

[build] make[2]: *** [hello_opencv.elf] Error 1

[build] make[1]: *** [CMakeFiles/hello_opencv.elf.dir/all] Error 2

[build] make: *** [all] Error 2

[build] CMakeFiles/hello_opencv.elf.dir/build.make:423: recipe for target ‘hello_opencv.elf’ failed

[build] CMakeFiles/Makefile2:554: recipe for target ‘CMakeFiles/hello_opencv.elf.dir/all’ failed

[build] Makefile:129: recipe for target ‘all’ failed

[build] Build finished with exit code 2

Was mach ich?
Mark

[PittyJ (Gast)]

app_main ergänzen.

z.B.

int app_main()
{
  return 0
}

[J. S. (jojos)]

Das ist ein Projekt mit ESP IDF Struktur, PIO erwartet ein src dir. Kann 
man aber in der platformio.ini anders einstellen.
https://docs.platformio.org/en/latest/frameworks/espidf.html?utm_source=docs.espressif.com#configuration