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1.4.0 -> 1.4.1 required the addition of the ip_info structure, which had
been deprecated. I could do that on user files, the module manufacturer
used that structure for internal stuff. Everything compiled
straightforward once I copied the sys_now() from their version of sys.h...
My journey stopped here, as at that point I discovered these people had
highly modified the lwIP stack for their needs, having many private
memory related functions, making my adventure quite unpleasant and
unportable.