编译工程遇到了错误提示

[msjlhz]

错误提示如下，有没有懂得大神解答一下，感谢！

Toolchain path: /esp32/crossTools/xtensa-esp32-elf/bin/xtensa-esp32-elf-gcc
Toolchain version: crosstool-ng-1.22.0-80-g6c4433a
Compiler version: 5.2.0
Python requirements from /esp32/sources/esp-idf/requirements.txt are satisfied.

Project is not inside a git repository, will not use 'git describe' to determine PROJECT_VER.
App "sd_card" version: 1
LD build/sd_card.elf
/esp32/demos/sd_card/build/esp32/libesp32.a(cpu_start.o):(.literal.main_task+0x18): undefined reference to `app_main'
/esp32/demos/sd_card/build/esp32/libesp32.a(cpu_start.o): In function `main_task':
/esp32/sources/esp-idf/components/esp32/cpu_start.c:515: undefined reference to `app_main'
collect2: error: ld returned 1 exit status
/esp32/sources/esp-idf/make/project.mk:520: recipe for target '/esp32/demos/sd_card/build/sd_card.elf' failed
make: *** [/esp32/demos/sd_card/build/sd_card.elf] Error 1

[ESP_Gargamel]

/esp32/demos/sd_card/build/esp32/libesp32.a(cpu_start.o):(.literal.main_task+0x18): undefined reference to `app_main'

你的 demo 里没有入口函数 app_main？

你可以与 idf examples 下的示例对比一下，或者你把你的 demo 提交上来。