Agree that this warning is harmless. It is not fixed yet in espressif/esp-idf master. I just filed an issue for it. (I could submit a fix, but that review process takes so long...) -- Steve On Sat, 14 Apr 2018, Mark Webb-Johnson wrote:
I see this too. I'm guessing it is a bug in the ESP IDF version we pulled at last merge.
I enabled the option for MD5 checksums on the partition table, for production builds, and it seems to be working (looking at the generated partitions.bin). It also validates correctly.
I think this is just a facility to disable the generation of MD5 checksums, and the MD5_OPT variable is not set empty when using MD5 checksums. Should not impact operation.
Once the next OTA firmware release goes out, I intend to try another upstream merge for the IDF. Just a bit scary as historically they have broken stuff.
Regards, Mark.
On 14 Apr 2018, at 6:38 AM, Stephen Casner <casner@acm.org> wrote:
Item 1: When running "make flash" I see the following warning:
Running make flash... /Users/casner/src/github/esp-idf/components/partition_table/Makefile.projbuild:16: warning: undefined variable `MD5_OPT' Flashing binaries to serial port /dev/cu.SLAB_USBtoUART (app at offset 0x10000)...
A grep for MD5_OPT in the esp-idf source tree only finds the two instances in Makefile.projbuild, so it looks like is not defined anywhere if CONFIG_PARTITION_TABLE_MD5=y.
Do others see this warning? If not, I must need to update something.