Using the new Arduino IDE for ESP8266 and found bugs, report them here

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By jasonharper
#74773 I'm trying to create a SoftAP-based ESP8266 application, using the Arduino environment. I can connect to the SoftAP just fine with my iPad, but none of numerous example programs will actually work with my old Windows XP laptop: it can connect, but never gets an IP address assigned.

Looking at the traffic in Wireshark, I see that the computer is sending DHCP Requests, and the module is actually responding with a DHCP Offer - but it's being sent to a destination IP address of 192.168.4.255, which is NOT an address that my computer would know to listen to until after it had already accepted the offer. As far as I know, that packet is supposed to be addressed to 255.255.255.255. (I don't know if the DHCP server is using the proper destination address with other computers, or whether they are simply ignoring the IP address at that point in the process.)

Is this a known bug? Any workarounds?
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By jasonharper
#74932 Turns out that the problem was due to the bogus option 43 that the DHCP server is including in the offer message for no apparent reason. WinXP has a known bug concerning the presence of this option; there was a hotfix for this (KB953761), but Microsoft no longer makes it available. I am able to connect and get an IP address now, just by commenting out the code in lwIP that sent that option (which was quite a pain, since the "compile from source" option for lwIP doesn't work under Windows without a lot of tweaking).

(On further research, having a DHCP Offer going to a subnet broadcast address is actually valid, although it isn't the preferred way.)