i am using -Wconditional-uninitialized flag and then i am getting some errrors from the library.

[ananta-code]

i am using -Wconditional-uninitialized flag and then i am getting some errrors from the library.

external/com_google_protobuf/src/google/protobuf/arena.cc:398:12: error: variable 'arena' may be uninitialized when used here [-Werror,-Wconditional-uninitialized]
return arena->AllocateAlignedWithCleanup(n, alloc_policy_.get());
^~~~~
external/com_google_protobuf/src/google/protobuf/arena.cc:395:21: note: initialize the variable 'arena' to silence this warning
SerialArena* arena;
^
= nullptr
1 error generated.

i want to filter out this error since it is coming from the library and i am using Bazel 5.0 and feature : build --features=external_include_paths but still i am seeing the above error from the library.

Could you please help me on this?

Originally posted by @ananta-code in #12009 (comment)

[sgowroji]

Hello @ananta-code, Can you please provide complete steps to reproduce the above error. Thanks !

[ananta-code]

Hello @ananta-code, Can you please provide complete steps to reproduce the above error. Thanks !

@sgowroji I have a bazel build and i am using clang compiler aruguments to build c++ app.
the bazel rc content is like this:

build --stamp
build --workspace_status_command bazel/get_workspace_status
build --features=external_include_paths
build --repo_env=BAZEL_CXXOPTS="-std=c++17:-Werror:-Wextra:-Wnon-virtual-dtor:-Woverloaded-virtual:-Wno-sign-compare:-Wunreachable-code:-Wno-unused-parameter:-Wno-error=missing-field-initializers:-Wno-error=deprecated-declarations:-Wno-error=ignored-qualifiers:-Wno-error=unused-variable:-Wno-error=unreachable-code:-Wno-error=implicit-fallthrough:-Wno-error=implicit-int-float-conversion:-Wno-unknown-warning-option:-Wno-error=unused-function:-Wconditional-uninitialized"

and i am building app with these compiler option and then getting error from the library.
ERROR: /home/temp/.cache/bazel/_bazel_sabre2/57c0574d1f367333dd959780f3f5b13f/external/com_google_protobuf/BUILD:155:11: Compiling src/google/protobuf/arena.cc [for host] failed: (Exit 1): clang-10 failed: error executing command /usr/bin/clang-10 -U_FORTIFY_SOURCE -fstack-protector -Wall -Wthread-safety -Wself-assign -fcolor-diagnostics -fno-omit-frame-pointer -g0 -O2 '-D_FORTIFY_SOURCE=1' -DNDEBUG -ffunction-sections ... (remaining 46 arguments skipped)

Use --sandbox_debug to see verbose messages from the sandbox and retain the sandbox build root for debugging
external/com_google_protobuf/src/google/protobuf/arena.cc:398:12: error: variable 'arena' may be uninitialized when used here [-Werror,-Wconditional-uninitialized]
return arena->AllocateAlignedWithCleanup(n, alloc_policy_.get());
^~~~~
external/com_google_protobuf/src/google/protobuf/arena.cc:395:21: note: initialize the variable 'arena' to silence this warning
SerialArena* arena;
^
= nullptr
1 error generated.

Since i am using features=external_include_paths i am not expecting this error from the library.

and in my BUILD i am loading these libraries.
load("@com_google_protobuf//:protobuf.bzl", "py_proto_library")
load("//bazel:plantuml.bzl", "plantuml")
load("//bazel:service.bzl", "service")
load("@com_github_grpc_grpc//bazel:cc_grpc_library.bzl", "cc_grpc_library")
load("@rules_cc//cc:defs.bzl", "cc_binary", "cc_library", "cc_proto_library", "cc_test")
load("@bazel_skylib//rules:copy_file.bzl", "copy_file")
load("@rules_proto//proto:defs.bzl", "proto_library")

[ananta-code]

@sgowroji thanks for your respone.
my issue is similar to #15762.
why you tagged it as not a bug.

also could you please help me on #15762