I am using the C++ connector, version 8.0.23 on Windows 10 Pro, under WSL Ubuntu 20.04.1. When I try to build my application, I get the following link error:
/usr/bin/ld: ../bin/lib/linux/Ubuntu20.04/x86_64-linux-gnu/libmysqlcppconn8-static.a(libcdk_foundation_socket_detail.cc.o): in function `cdk::foundation::connection::detail::srv_list(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)':
(.text+0x9b2): undefined reference to `__res_nsearch'
/usr/bin/ld: (.text+0x9fa): undefined reference to `ns_initparse'
/usr/bin/ld: (.text+0xa5a): undefined reference to `ns_parserr'
/usr/bin/ld: (.text+0xac8): undefined reference to `__dn_expand'
collect2: error: ld returned 1 exit status
The compiler is:
g++ (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Note that I am statically linking mysqlcpp, and I have -lresolv included in my command with a -L switch pointing to the dir with all the lib* files, and further, libresolv.a and .so are in that directory. My assumption is that this is a dynamic link to libresolv.so.
Further note that if I change to statically linking to libresolv by taking out -lresolv and instead using /usr/lib/x86_64-linux-gnu/libresolv.a in the linker, I do not get the error and my program works.
Finally, what is most puzzling, is that if I specify -lresolv AFTER my static link reference to mysqlcpp (in the error above, the switch was BEFORE the static link reference), then I do not get the error.
Note that I do not see this behavior using CLANG on osx.
Any ideas? Bug in g++? Does switch order matter? Should it?
/usr/bin/ld: ../bin/lib/linux/Ubuntu20.04/x86_64-linux-gnu/libmysqlcppconn8-static.a(libcdk_foundation_socket_detail.cc.o): in function `cdk::foundation::connection::detail::srv_list(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)':
(.text+0x9b2): undefined reference to `__res_nsearch'
/usr/bin/ld: (.text+0x9fa): undefined reference to `ns_initparse'
/usr/bin/ld: (.text+0xa5a): undefined reference to `ns_parserr'
/usr/bin/ld: (.text+0xac8): undefined reference to `__dn_expand'
collect2: error: ld returned 1 exit status
The compiler is:
g++ (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Note that I am statically linking mysqlcpp, and I have -lresolv included in my command with a -L switch pointing to the dir with all the lib* files, and further, libresolv.a and .so are in that directory. My assumption is that this is a dynamic link to libresolv.so.
Further note that if I change to statically linking to libresolv by taking out -lresolv and instead using /usr/lib/x86_64-linux-gnu/libresolv.a in the linker, I do not get the error and my program works.
Finally, what is most puzzling, is that if I specify -lresolv AFTER my static link reference to mysqlcpp (in the error above, the switch was BEFORE the static link reference), then I do not get the error.
Note that I do not see this behavior using CLANG on osx.
Any ideas? Bug in g++? Does switch order matter? Should it?