libm.a problem: missing __ieee754_remainder function?

[minyk]

Like esp8266/Arduino#612, When I using Adafruit's Ultimate GPS library, I met below during complie:

/Users/minyk/Documents/Arduino/hardware/espressif/esp32/tools/sdk/lib/libm.a(lib_a-e_fmod.o):(.literal+0x0): undefined reference to `__ieee754_remainder'
/Users/minyk/Documents/Arduino/hardware/espressif/esp32/tools/sdk/lib/libm.a(lib_a-e_fmod.o): In function `__ieee754_fmod':
/home/ivan/freertos/smpemu/newlib/newlib_xtensa-2.2.0/xtensa-esp108-elf/newlib/libm/math/../../../.././newlib/libm/math/e_fmod.c:38: undefined reference to `__ieee754_remainder'
collect2: error: ld returned 1 exit status
exit status 1
Error compiling for board ESP32 Dev Module.

When I comment out fmod from the GPS library code, it successfully compile.

Thanks.

[nkolban]

It is likely that this issue is not directly related to the Arduino functions built on top of ESP-IDF but rather with ESP-IDF itself. See:

espressif/esp-idf#83

[minyk]

@nkolban Thank you!