libwebsockets - undefined reference to 'errno'

[teckhaokoh]

Hi, anyone have successfully build esp32 with libwebsockets?

I'm using esp-idf release/v4.2, with the latest libwebsockets added as submodule in the components folder.

I'm able to execute the compilation till the last step, building the xxxx.elf, but it returned error as below:

/home/user/.espressif/tools/xtensa-esp32-elf/esp-2020r1-8.2.0/xtensa-esp32-elf/bin/../lib/gcc/xtensa-esp32-elf/8.2.0/../../../../xtensa-esp32-elf/bin/ld: /mnt/hgfs/vmshared/ft04/build/libwebsockets/liblibwebsockets.a(output.c.o):(.literal.lws_ssl_capable_read_no_ssl+0x0): undefined reference to `errno'
collect2: error: ld returned 1 exit status
/home/user/esp/esp-4.2/esp-idf/make/project.mk:563: recipe for target '/mnt/hgfs/vmshared/ft04/build/easyioft.elf' failed
make: *** [/mnt/hgfs/vmshared/ft04/build/easyioft.elf] Error 1