Having trouble linking on RHEL 8.6

[argo1221]

I am trying to compile and link this older version, because our customer is using a version of RHEL that uses an older gcc.
Here are my includes:
#include <libpq-fe.h>
#include <pqxx/pqxx>

Here is the code. This was put in as a placeholder just to get thing up and running:
pqxx::connection c("dbname=onc user=postgres hostaddr=10.17.12.69 port=5432");
//pqxx::work w(c);
I am eventually going to connect to a different IP address and modify an existing table.
This is what happens when I try to build it.

oceus/OCEUS_OSUtils.o: In function pqxx::basic_connection_base<pqxx::connect_direct>::~basic_connection_base()': OCEUS_OSUtils.cpp:(.text._ZN4pqxx21basic_connection_baseINS_14connect_directEED2Ev[_ZN4pqxx21basic_connection_baseINS_14connect_directEED2Ev]+0x15): undefined reference to pqxx::connection_base::close()'
oceus/OCEUS_OSUtils.o: In function pqxx::basic_connection_base<pqxx::connect_direct>::basic_connection_base(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)': OCEUS_OSUtils.cpp:(.text._ZN4pqxx21basic_connection_baseINS_14connect_directEEC2ERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE[_ZN4pqxx21basic_connection_baseINS_14connect_directEEC2ERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE]+0x6c): undefined reference to pqxx::connection_base::init()'
oceus/OCEUS_OSUtils.o: In function pqxx::connection_base::connection_base(pqxx::connectionpolicy&)': OCEUS_OSUtils.cpp:(.text._ZN4pqxx15connection_baseC2ERNS_16connectionpolicyE[_ZN4pqxx15connection_baseC2ERNS_16connectionpolicyE]+0xf5): undefined reference to int pqxx::internal::check_library_version<6, 4>()'
OCEUS_OSUtils.cpp:(.text._ZN4pqxx15connection_baseC2ERNS_16connectionpolicyE[_ZN4pqxx15connection_baseC2ERNS_16connectionpolicyE]+0x128): undefined reference to pqxx::connection_base::clearcaps()' oceus/OCEUS_OSUtils.o: In function pqxx::connect_direct::connect_direct(std::__cxx11::basic_string<char, std::char_traits, std::allocator > const&)':
OCEUS_OSUtils.cpp:(.text._ZN4pqxx14connect_directC2ERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE[_ZN4pqxx14connect_directC2ERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE]+0x1d): undefined reference to pqxx::connectionpolicy::connectionpolicy(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' OCEUS_OSUtils.cpp:(.text._ZN4pqxx14connect_directC2ERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE[_ZN4pqxx14connect_directC2ERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE]+0x28): undefined reference to vtable for pqxx::connect_direct'
oceus/OCEUS_OSUtils.o: In function pqxx::connect_direct::~connect_direct()': OCEUS_OSUtils.cpp:(.text._ZN4pqxx14connect_directD2Ev[_ZN4pqxx14connect_directD2Ev]+0x11): undefined reference to pqxx::connectionpolicy::~connectionpolicy()'
clang-13: error: linker command failed with exit code 1 (use -v to see invocation)
make[1]: *** [make-linux.mk:350: one] Error 1
make[1]: Leaving directory '/Projects/oncast_sandbox/zerotierone'
make: *** [make-linux.mk:392: central-controller] Error 2
make: Leaving directory '/Projects/oncast_sandbox/zerotierone'

Here is the relevant section of the makefile:
central-controller: FORCE
make -j4 LDLIBS="-L/usr/local/pgsql/lib/ -lpq -L/usr/local/lib/ -Lext/librabbitmq/centos_x64/lib/ -lrabbitmq" CXXFLAGS="-I/usr/local/pgsql/include -I./ext/librabbitmq/centos_x64/include -fPIC" DEFS="-DZT_CONTROLLER_USE_LIBPQ -DZT_CONTROLLER" ZT_OFFICIAL=1 ZT_USE_X64_ASM_ED25519=1 one

I have built postgresql 10.22 from source, as well as libpqxx.

The libpxx libraries are installed at /usr/local/lib.
If you have any clues as to what is going on I would appreciate it.
Thanks!!

[tt4g]

It looks like pqxx is not linked by LDLIBS.

[jtv]

That is an old libpqxx version indeed. Off the top of my head, I'd guess it was 6.x at the latest, compiling with C++11 or older. Just as a suggestion, there may be a backported version of gcc — although of course your customer may have rules that prohibit backports.

As @tt4g said, you don't seem to be linking in libpqxx at all! Link -lpqxx first, then -lpq. It looks as if that would fix the problems we're seeing here.

On a side note... Don't include <libpq-fe.h>. The libpqxx source code will do that as needed, and the libpqxx headers don't even need it at all. Once you have libpqxx compiled, you could theoretically build your application without the postgres headers installed anywhere. (Unless the application itself makes use of the C-level libpq API separately from its use of libpqxx, of course.)

[jtv]

@argo1221 does this solve your problem?

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There has been no activity on this ticket. Consider closing it.

[jtv]

OK, OK, we'll close it then.