//src/google/protobuf/json:parser depends on @com_google_googletest//:gtest_main

[monkeynova]

//src/google/protobuf/json:parser is a library (and transitively included in //:protobuf). This means any attempt to link with //:protobuf brings in an implementation of main which could be called instead of the caller's main.

The chain I see in my local repository (where I'm having the incorrect main called) is

... local dependencies...
@com_google_protobuf//:protobuf
@com_google_protobuf//src/google/protobuf/util:json_util
@com_google_protobuf//src/google/protobuf/json:json
@com_google_protobuf//src/google/protobuf/json:parser
@com_google_googletest//:gtest_main
@com_google_googletest//:googlemock/src/gmock_main.cc

This is the location of the dependency I think is in error: https://github.com/protocolbuffers/protobuf/blob/main/src/google/protobuf/json/BUILD.bazel#L197

[deannagarcia]

I need more information to help diagnose this. Please fill out our bug template form with how you're building, where you are running this, and the exact error logs you see.

In general, we have many other dependencies on gtest_main that we haven't seen any issues with.

[monkeynova]

I'm happy to fill out the template if that helps you, but I believe that any library that depends on :gtest_main is a bug (even if it happens to work in some circumstances) since it would include multiple definitions of main during linking.

What version of protobuf and what language are you using?
Version: main/v3.6.0/v3.5.0 etc. (NOTE: please try updating to the latest version of protoc/runtime possible beforehand to attempt to resolve your problem)
Language: C++

What operating system (Linux, Windows, ...) and version?
OSX (10.15.7), Linux (5.15.74-v8+)

What runtime / compiler are you using (e.g., python version or gcc version)
llvm (OSX), gcc (Linux)

What did you do?
Steps to reproduce the behavior:
Test ://github.com/monkeynova/logic-solver
bazelisk test //sudoku:single_line_test
Works - as in all tests pass.
Update WORKSPACE to point commit including the new dependency (32bea52)
perl -spi -e 's/66ed6dd75b0b5f0d62a9bf90509638f380cbcd7f/15dff733cf40d6ecdac8b66d5202bb23dd125d43/g' WORKSPACE
Test ://github.com/monkeynova/logic-solver.git
bazelisk test //sudoku:single_line_test

• Fails* - (tests use gtest_main rather than the main I've intended to link which behaves similarly, see details below...)

What did you expect to see
I expect when I link a library to not have an implementation of main included

What did you see instead?
A main other than the one I authored was called by the system

Make sure you include information that can help us debug (full error message, exception listing, stack trace, logs).
Failure test log (head)

exec ${PAGER:-/usr/bin/less} "$0" || exit 1
Executing tests from //sudoku:single_line_test
-----------------------------------------------------------------------------
Running main() from gmock_main.cc
[==========] Running 2 tests from 1 test suite.
[----------] Global test environment set-up.
[----------] 2 tests from Puzzle
[ RUN      ] Puzzle.RightAnswer

Success test log (head)

darwin-opt/testlogs/sudoku/single_line_test/test.log
exec ${PAGER:-/usr/bin/less} "$0" || exit 1
Executing tests from //sudoku:single_line_test
-----------------------------------------------------------------------------
InitMain(/private/var/tmp/_bazel_keith/7aeb99f7f348857a60e16b07cad11c5b/sandbox/darwin-sandbox/715/execroot/com_monkeynova_logic_solver/bazel-out/darwin-opt/bin/sudoku/single_line_test.runfiles/com_monkeynova_logic_solver/sudoku/single_line_test)
[==========] Running 2 tests from 1 test suite.
[----------] Global test environment set-up.
[----------] 2 tests from Puzzle

[johanbrandhorst]

In release v3.22.0 (or v4.22.0?) this is causing a build error in the grpc-gateway:

ERROR: /home/vscode/.cache/_grpc_gateway_bazel/external/com_google_protobuf/src/google/protobuf/json/BUILD.bazel:199:11: no such package '@com_google_googletest//': The repository '@com_google_googletest' could not be resolved: Repository '@com_google_googletest' is not defined and referenced by '@com_google_protobuf//src/google/protobuf/json:parser'

Full testlog.

I've worked around it by adding com_google_googletest as a dependency in my WORKSPACE, but it doesn't look to me like this was mentioned in the release notes.