Unity XCode build linker command failed with exit code 1

I used unity 2018.3.5 and xcode 10.1 Who can fix this error for me? Undefined symbols for architecture armv7: "_getIPv6", referenced from: _IOSIpv6_getIPv6_m9EC241BE5A4FA66C88AC51CBA9EAC10C554BA989 in Bulk_Assembly-CSharp_1.o (maybe you meant: _IOSIpv6_getIPv6_m9EC241BE5A4FA66C88AC51CBA9EAC10C554BA989) ld: symbol(s) not found for architecture armv7 clang: error: linker command failed with exit code 1 (use -v to see invocation)