This message was posted on behalf of Intel Corporation
Thanks for reaching out!
I understand, this is an unexpected behavior. Since you were able to compile your code successfully using mraa 1.4.0 + upm 0.8.0, I'd suggest you to go back to these versions. You can do so, by following these instructions:
opkg remove mraa --force-removal-of-dependent-packages
####The line above should remove both mraa and upm, in case it doesn't enter it again but with upm
opkg install mraa_1.4.0_i586.ipk
opkg install upm_0.8.0_i586.ipk
Now you will have mraa 1.4.0 + upm 0.8.0 and you'll be able to continue working with your application. As I mentioned this behavior is not usual, so, I suggest you to report it in upm's Github (https://github.com/intel-iot-devkit/upm/issues).
I hope this helps.