Error at linking qr_recognize

[yshinjp]

Hi,

I can't build this project as follows.

[820/821] Linking CXX executable camera.elf
FAILED: camera.elf
cmd.exe /C "cd . && C:\Users\yshin.espressif\tools\xtensa-esp32-elf\esp-2019r2-8.2.0\xtensa-esp32-elf\bin\xtensa-esp32-elf-g++.exe -mlongcalls -Wno-frame-address -O3 -DNDEBUG -nostdlib @CMakeFiles\camera.elf.rsp -o camera.elf && cd ."
c:/users/yshin/.espressif/tools/xtensa-esp32-elf/esp-2019r2-8.2.0/xtensa-esp32-elf/bin/../lib/gcc/xtensa-esp32-elf/8.2.0/../../../../xtensa-esp32-elf/bin/ld.exe: esp-idf/main/libmain.a(main.c.obj):(.literal.app_main+0x18): undefined reference to `qr_recognize'
collect2.exe: error: ld returned 1 exit status
ninja: build stopped: subcommand failed.
ninja failed with exit code 1

Do I have to correct Makefile ?

Thank you.

Yasuto,