Undefined symbols in poco library

[eduardfrigola]

Hi everyone,
ofxPoco is not working on my machine (latest pull from main git, and from apotecary submodule, recent ./download_libs.sh)
macOS 10.14.6
Xcode 11.3.1

I get the following error:
Undefined symbols for architecture x86_64: "___darwin_check_fd_set_overflow", referenced from: Poco::Net::SocketImpl::poll(Poco::Timespan const&, int) in PocoNet.a(SocketImpl.o) ld: symbol(s) not found for architecture x86_64

Seems the same problem as curl had some days ago, compatibility issues with older xcode versions: #176.

Eduard

[roymacdonald]

Hi @eduardfrigola
were you able to fix this?
I also run into it and from what I read it is a problem with xcode.
Although I was able to compile and run by adding the following
-Wl,-U,___darwin_check_fd_set_overflow as a linker flag. In Xcode go to the build settings and add it to "Other Linker Flags".

No idea what implications this has.

[eduardfrigola]

Hi @roymacdonald !
What I did is copying the poco libraries from of10.x release, as they are not updated for bigsur, that has the new xcode version... And no darwin error with them.

[roymacdonald]

Hmmm, interesting. So the problem has to do with which OS SDK the Poco library was compiled?

[eduardfrigola]

I think who knows what everything means is @ofTheo, seeing his insights on this for curl lib in this issue #176

[roymacdonald]

sure. I checked the ofxPoco libs from 0.10.1 and all the headers are the same as the ones in the newest release but the compiled libs are all different, so I guess that in which OS it is compiled matters