Building with bazel error: "ar: libdeps specified more than once" or "undefined reference to PQ"

[manoelmenezes]

Hello,
Could you help me solving the following issue? Thank you!
I am trying to build it with bazel.

Machine:
Linux 6.1.0-18-cloud-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.76-1 (2024-02-01) x86_64 GNU/Linux

I already installed:

sudo apt install postgresql postgresql-contrib
sudo apt-get install -y libpq-dev

My WORKSPACE file:

http_archive(
    name = "rules_foreign_cc",
    patch_args = ["-p1"],
    sha256 = "62e364a05370059f07313ec46ae4205af23deb00e41f786f3233a98098c7e636",
    strip_prefix = "rules_foreign_cc-ae4ff42901354e2da8285dac4be8329eea2ea96a",
    url = "https://github.com/bazelbuild/rules_foreign_cc/archive/ae4ff42901354e2da8285dac4be8329eea2ea96a.tar.gz",  # v 0.7.1
)

load("@rules_foreign_cc//foreign_cc:repositories.bzl", "rules_foreign_cc_dependencies")

rules_foreign_cc_dependencies(
    register_built_tools = True,
)

new_git_repository(
    name = "pqxx",
    build_file = "//:libpqxx.BUILD",
    commit = "9d2a459f76f52ea0df7b9b306b27fba84bb82e5f",
    remote = "https://github.com/jtv/libpqxx",
)

libpqxx.BUILD:

load("@rules_foreign_cc//foreign_cc:defs.bzl", "cmake")

package(
    default_visibility = ["//visibility:public"],
)

filegroup(
    name = "all_srcs",
    srcs = glob(["**"]),
    visibility = ["//:__pkg__"],
)

cmake(
    name = "pqxx",
    build_args = [
        "--verbose",
    ],
    cache_entries = {
        "CMAKE_C_FLAGS": "-fPIC",
        "CMAKE_STATIC_LINKER_FLAGS": "-lpqxx -lpq",
        "BUILD_SHARED_LIBS": "off",
         "PostgreSQL_TYPE_INCLUDE_DIR": "/usr/include/postgresql",
        "PostgreSQL_INCLUDE_DIR": "/usr/include/postgresql",
         "PostgreSQL_LIBRARY": "/usr/lib/x86_64-linux-gnu/libpq.so",
    },
    lib_source = "@pqxx//:all_srcs",
    visibility = ["//visibility:public"],
    out_static_libs = ["libpqxx.a"],
    targets = ["pqxx"],
)

The error is:

...
[ 95%] Building CXX object src/CMakeFiles/pqxx.dir/wait.cxx.o
cd /home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/bazel-out/k8-fastbuild/bin/external/pqxx/pqxx.build_tmpdir/src && /home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/gcc_toolchain_x86_64/bin/gcc --sysroot=/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/sysroot_x86_64/  -I/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/bazel-out/k8-fastbuild/bin/external/pqxx/pqxx.build_tmpdir/include -I/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/pqxx/include -I/usr/include/postgresql -fstack-protector -Wall -Wunused-but-set-parameter -Wno-free-nonheap-object -fno-omit-frame-pointer -std=c++0x --sysroot /home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/sysroot_x86_64/ -no-canonical-prefixes -fno-canonical-system-headers -Wno-builtin-macro-redefined -D__DATE__=\"redacted\" -D__TIMESTAMP__=\"redacted\" -D__TIME__=\"redacted\" -fdiagnostics-color=always -nostdinc -nostdinc++ -B/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/gcc_toolchain_x86_64/bin -isystem/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/sysroot_x86_64//include/c++/10.3.0 -isystem/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/sysroot_x86_64//include/c++/10.3.0/x86_64-linux -isystem/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/sysroot_x86_64//lib/gcc/x86_64-linux/10.3.0/include-fixed -isystem/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/sysroot_x86_64//lib/gcc/x86_64-linux/10.3.0/include -isystem/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/sysroot_x86_64//usr/include -std=c++17 -O3 -DNDEBUG -std=c++17 -MD -MT src/CMakeFiles/pqxx.dir/wait.cxx.o -MF CMakeFiles/pqxx.dir/wait.cxx.o.d -o CMakeFiles/pqxx.dir/wait.cxx.o -c /home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/pqxx/src/wait.cxx
x86_64-linux-gcc: WARNING: unsafe header/library path used in cross-compilation: '-I/usr/include/postgresql'
[100%] Linking CXX static library libpqxx-7.9.a
cd /home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/bazel-out/k8-fastbuild/bin/external/pqxx/pqxx.build_tmpdir/src && /home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/external/cmake-3.22.1-linux-x86_64/bin/cmake -P CMakeFiles/pqxx.dir/cmake_clean_target.cmake
cd /home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/bazel-out/k8-fastbuild/bin/external/pqxx/pqxx.build_tmpdir/src && /home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/external/cmake-3.22.1-linux-x86_64/bin/cmake -E cmake_link_script CMakeFiles/pqxx.dir/link.txt --verbose=1
/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/external/gcc_toolchain_x86_64/bin/ar qc libpqxx-7.9.a -lpqxx -lpq CMakeFiles/pqxx.dir/array.cxx.o CMakeFiles/pqxx.dir/binarystring.cxx.o CMakeFiles/pqxx.dir/blob.cxx.o CMakeFiles/pqxx.dir/connection.cxx.o CMakeFiles/pqxx.dir/cursor.cxx.o CMakeFiles/pqxx.dir/encodings.cxx.o CMakeFiles/pqxx.dir/errorhandler.cxx.o CMakeFiles/pqxx.dir/except.cxx.o CMakeFiles/pqxx.dir/field.cxx.o CMakeFiles/pqxx.dir/largeobject.cxx.o CMakeFiles/pqxx.dir/notification.cxx.o CMakeFiles/pqxx.dir/params.cxx.o CMakeFiles/pqxx.dir/pipeline.cxx.o CMakeFiles/pqxx.dir/result.cxx.o CMakeFiles/pqxx.dir/robusttransaction.cxx.o CMakeFiles/pqxx.dir/row.cxx.o CMakeFiles/pqxx.dir/sql_cursor.cxx.o CMakeFiles/pqxx.dir/strconv.cxx.o CMakeFiles/pqxx.dir/stream_from.cxx.o CMakeFiles/pqxx.dir/stream_to.cxx.o CMakeFiles/pqxx.dir/subtransaction.cxx.o CMakeFiles/pqxx.dir/time.cxx.o CMakeFiles/pqxx.dir/transaction.cxx.o CMakeFiles/pqxx.dir/transaction_base.cxx.o CMakeFiles/pqxx.dir/util.cxx.o CMakeFiles/pqxx.dir/version.cxx.o CMakeFiles/pqxx.dir/wait.cxx.o
/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/external/gcc_toolchain_x86_64_files/bin/x86_64-linux-ar: libdeps specified more than once
make[3]: *** [src/CMakeFiles/pqxx.dir/build.make:514: src/libpqxx-7.9.a] Error 1
make[3]: Leaving directory '/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/bazel-out/k8-fastbuild/bin/external/pqxx/pqxx.build_tmpdir'
make[2]: *** [CMakeFiles/Makefile2:134: src/CMakeFiles/pqxx.dir/all] Error 2
make[2]: Leaving directory '/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/bazel-out/k8-fastbuild/bin/external/pqxx/pqxx.build_tmpdir'
make[1]: *** [CMakeFiles/Makefile2:141: src/CMakeFiles/pqxx.dir/rule] Error 2
make[1]: Leaving directory '/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/79/execroot/__main__/bazel-out/k8-fastbuild/bin/external/pqxx/pqxx.build_tmpdir'
make: *** [Makefile:189: pqxx] Error 2

If I remove "CMAKE_STATIC_LINKER_FLAGS": "-lpqxx -lpq", from the file libpqxx.BUILD. It fails with (a lot of undefined reference to PQ - the error below has been truncated):

INFO: Analyzed target //main:rinha (1 packages loaded, 355 targets configured).
ERROR: /home/manoelmenezes/projects/rinha-backend-2024-q1/main/BUILD:3:10: Linking main/rinha failed: (Exit 1): gcc failed: error executing CppLink command (from target //main:rinha) 
  (cd /home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/sandbox/linux-sandbox/81/execroot/__main__ && \
  exec env - \
    PATH=/home/manoelmenezes/.cache/bazelisk/downloads/sha256/1ca5d63a30244788ff9a5b7c35584f57111a68c82bbff2929ec7b2e99f35c7a8/bin:/home/manoelmenezes/bazelisk/bazelisk-linux-amd64:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games \
    PWD=/proc/self/cwd \
  external/gcc_toolchain_x86_64/bin/gcc -o bazel-out/k8-fastbuild/bin/main/rinha bazel-out/k8-fastbuild/bin/main/_objs/rinha/main.pic.o bazel-out/k8-fastbuild/bin/model/libclient-service.a bazel-out/k8-fastbuild/bin/external/served/libserved.a bazel-out/k8-fastbuild/bin/external/boost/libasio.a bazel-out/k8-fastbuild/bin/external/boost/libchrono.a bazel-out/k8-fastbuild/bin/external/boost/libsystem.a bazel-out/k8-fastbuild/bin/external/boost/libcontainer.a bazel-out/k8-fastbuild/bin/external/boost/libatomic.a bazel-out/k8-fastbuild/bin/external/boost/libatomic_sse.a bazel-out/k8-fastbuild/bin/external/boost/libregex.a bazel-out/k8-fastbuild/bin/external/boost/libexception.a bazel-out/k8-fastbuild/bin/external/pqxx/pqxx/lib/libpqxx.a -lpthread -Wl,-S -Wl,-z,relro,-z,now -pass-exit-codes -lm -lstdc++ --sysroot external/sysroot_x86_64/ -Bexternal/gcc_toolchain_x86_64/bin -Bexternal/sysroot_x86_64//usr/lib -Bexternal/sysroot_x86_64//lib64 -Lexternal/sysroot_x86_64//lib64 -Lexternal/sysroot_x86_64//usr/lib -Lexternal/sysroot_x86_64//lib/gcc/x86_64-linux/10.3.0)
# Configuration: 0e913ec885832ba80eb84357b2922ef6ed6bd55134ad82350d1f632bf75f4fa4
# Execution platform: @@local_config_platform//:host

Use --sandbox_debug to see verbose messages from the sandbox and retain the sandbox build root for debugging
/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/external/gcc_toolchain_x86_64_files/bin/x86_64-linux-ld: bazel-out/k8-fastbuild/bin/external/pqxx/pqxx/lib/libpqxx.a(connection.cxx.o): in function `pqxx::connection::connection(pqxx::connection::connect_mode, pqxx::zview)':
connection.cxx:(.text+0x5e9): undefined reference to `PQconnectStart'
/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/external/gcc_toolchain_x86_64_files/bin/x86_64-linux-ld: connection.cxx:(.text+0x63f): undefined reference to `PQstatus'
/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/external/gcc_toolchain_x86_64_files/bin/x86_64-linux-ld: bazel-out/k8-fastbuild/bin/external/pqxx/pqxx/lib/libpqxx.a(connection.cxx.o): in function `pqxx::connection::poll_connect()':
connection.cxx:(.text+0x693): undefined reference to `PQconnectPoll'
/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/external/gcc_toolchain_x86_64_files/bin/x86_64-linux-ld: connection.cxx:(.text+0x6bc): undefined reference to `PQstatus'
/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/external/gcc_toolchain_x86_64_files/bin/x86_64-linux-ld: bazel-out/k8-fastbuild/bin/external/pqxx/pqxx/lib/libpqxx.a(connection.cxx.o): in function `pqxx::connection::sock() const &':
connection.cxx:(.text+0x7cd): undefined reference to `PQsocket'

...

/home/manoelmenezes/.cache/bazel/_bazel_manoelmenezes/67983900e4065458c8253806ac6d53ac/external/gcc_toolchain_x86_64_files/bin/x86_64-linux-ld: bazel-out/k8-fastbuild/bin/external/pqxx/pqxx/lib/libpqxx.a(util.cxx.o): in function `pqxx::describe_thread_safety()':
util.cxx:(.text.unlikely+0x330): undefined reference to `PQisthreadsafe'
collect2: error: ld returned 1 exit status

[tt4g]

From the build message, it looks like you are building pqxx.
Isn't -lpqxx unnecessary?

BTW. It is recommended that you ask questions about how to use Bazel in the Bazel community.

[jtv]

(It is normal that if you remove -lpq you get these link errors about missing functions like PQexec() etc. You do need the -lpq.)

[manoelmenezes]

thank you @jtv . Do you know how to solve the issue of "ar: libdeps specified more than once"? this error happens when -lpq is included.

[jtv]

I'm sorry, I have nothing beyond what @tt4g already mentioned. I don't know bazel, and it's hard to read those long command lines on my phone screen.

[tt4g]

I don't know Bazel's working specifications, but if Bazel is running CMake to build libpqxx, isn't the CMAKE_STATIC_LINKER_FLAGS variable not needed?
I think you are reporting a ar: libdeps specified more than once error because you are also adding the CMAKE_STATIC_LINKER_FLAGS linker option -lpq within CMake.

[jtv]

@manoelmenezes did you try @tt4g's suggestion? I have no further ideas I'm afraid. I've never worked with Bazel.

[jtv]

@manoelmenezes this looks like may also be a simple command line problem at its core. Can you see the command line that cmake produced for linking?

We're getting a bunch of bug reports now from people who run some variant of g++ -lpqxx -lpq myapp.cxx or g++ myapp.cxx -lpq -lpqxx, when they need to use the g++ myapp.cxx -lpqxx -lpq ordering instead.

[jtv]

It's been a while. I would guess that the problem has been resolved... @manoelmenezes did you ever find out what the problem was?

I'd like to close this ticket if so, but it'd be nice to have the solution for future readers.