GH-50868: [C++][CI] Suppress deprecated Abseil API warnings for GCS on macOS

[hiroyuki-sato]

Rationale for this change

Around August 10, 2026, the ARM64 macOS GLib & Ruby job in this project started failing.

The failure appears to have been caused by the Abseil version used when building the bundled google-cloud-cpp on macOS being updated to 20260526.0.

https://github.com/Homebrew/homebrew-core/blob/3decf2e9073cb08af3b4d5be7623f333f41fa3cc/Formula/a/abseil.rb

In Abseil LTS 20260526.0, many polyfill types and related APIs provided for pre-C++17 environments were marked as deprecated. Users are encouraged to migrate to the corresponding C++ standard library APIs.

https://github.com/abseil/abseil-cpp/releases/tag/20260526.0

The build failure occurs at the following code in google-cloud-cpp:

/Users/runner/work/arrow/arrow/build/cpp/_deps/google_cloud_cpp-src/google/cloud/stream_range.h:208:11: error: 'visit<UnpackVariant, std::variant<google::cloud::Status, google::cloud::storage::ObjectMetadata>>' is deprecated [-Werror,-Wdeprecated-declarations]
208 | absl::visit(UnpackVariant{*this}, std::move(v));
| ^

absl::visit has not been removed, but using it with Abseil 20260526.0 produces a deprecation warning. This would normally remain a warning, but Apache Arrow's CI uses -Werror, which causes the deprecation warning to be treated as a compilation error.

For C++17 and later, using std::visit is recommended:

std::visit(UnpackVariant{*this}, std::move(v));

However, absl::visit is still used in the latest google-cloud-cpp source.

https://github.com/googleapis/google-cloud-cpp/blob/main/google/cloud/stream_range.h#L206-L208

A fundamental fix will likely be required in google-cloud-cpp.

What changes are included in this PR?

• Add -Wno-error=deprecated-declarations to avoid build failures caused by deprecation warnings.
• Skip the red-arrow-flight tests on macOS because they currently fail. This will be addressed in a separate issue.

Are these changes tested?

Yes.

Are there any user-facing changes?

No.

• GitHub Issue: [C++] deprecated-declarations warnings in bundled google-cloud-cpp #50868

[github-actions]

⚠️ GitHub issue #50886has been automatically assigned in GitHub to PR creator.

[hiroyuki-sato]

Someone is referencing abseil/20260526.0 ex) protobuf or grpc, something
https://github.com/apache/arrow/actions/runs/31952314361/job/95177575907#step:12:1153

[hiroyuki-sato]

Build passed

diff --git a/.github/workflows/ruby.yml b/.github/workflows/ruby.yml
index 2794d55ba8..afdc115287 100644
--- a/.github/workflows/ruby.yml+++ b/.github/workflows/ruby.yml@@ -158,6 +158,8 @@ jobs:
ARROW_WITH_SNAPPY: ON
ARROW_WITH_ZLIB: ON
ARROW_WITH_ZSTD: ON
+ absl_SOURCE: BUNDLED+ ARROW_DEPENDENCY_SOURCE: BUNDLED
steps:
- name: Checkout Arrow
uses: actions/checkout@v7

[github-actions]

⚠️ GitHub issue #50868has been automatically assigned in GitHub to PR creator.

[hiroyuki-sato]

I believe the two CI failures are unrelated to this PR.

I tried the following three approaches. Approaches 1 and 3 worked, while approach 2 failed to build.
Thank you @kou

The current PR implements approach 3.

1. Use the bundled Abseil

• Use the bundled Abseil 20250127.0 for the ARM64 macOS GLib & Ruby build.
• Skip the red-arrow-flight tests on macOS because they fail.

With this approach, a bit more work is needed because Protobuf and gRPC still appear to use the Homebrew version of Abseil.

diff --git a/.github/workflows/ruby.yml b/.github/workflows/ruby.yml
index 2794d55ba8..370a161e6d 100644
--- a/.github/workflows/ruby.yml+++ b/.github/workflows/ruby.yml@@ -158,6 +158,14 @@ jobs:
ARROW_WITH_SNAPPY: ON
ARROW_WITH_ZLIB: ON
ARROW_WITH_ZSTD: ON
+ absl_SOURCE: BUNDLED
steps:
- name: Checkout Arrow
uses: actions/checkout@v7
diff --git a/c_glib/test/flight-sql/test-client.rb b/c_glib/test/flight-sql/test-client.rb
index 631eb3d542..1ed7f7e6e4 100644
--- a/c_glib/test/flight-sql/test-client.rb+++ b/c_glib/test/flight-sql/test-client.rb@@ -23,7 +23,7 @@ class TestFlightSQLClient < Test::Unit::TestCase
@server = nil
omit("Arrow Flight SQL is required") unless defined?(ArrowFlightSQL)
omit("Unstable on Windows") if Gem.win_platform?
- omit("Unstable on x86_64 macOS") if /x86_64-darwin/.match?(RUBY_PLATFORM)+ omit("Unstable on macOS") if /darwin/.match?(RUBY_PLATFORM)
@server = Helper::FlightSQLServer.new
host = "127.0.0.1"
location = ArrowFlight::Location.new("grpc://#{host}:0")

2. Pass compiler flags

I couldn't get this approach to build, so I abandoned it.

diff --git a/cpp/src/arrow/filesystem/gcsfs.cc b/cpp/src/arrow/filesystem/gcsfs.cc
index ffeba9eadc..b7b13aff7d 100644
--- a/cpp/src/arrow/filesystem/gcsfs.cc+++ b/cpp/src/arrow/filesystem/gcsfs.cc@@ -353,7 +353,9 @@ class GcsFileSystem::Impl {
// "Directory" convention, so if there is at least one object that
// matches the prefix we assume it is a directory.
std::string canonical = internal::EnsureTrailingSlash(path.object);
+ ARROW_SUPPRESS_DEPRECATION_WARNING
auto list_result = client_.ListObjects(path.bucket, gcs::Prefix(canonical));
+ ARROW_UNSUPPRESS_DEPRECATION_WARNING
for (auto&& object_metadata : list_result) {
if (!object_metadata) {

Log: https://github.com/apache/arrow/actions/runs/32109702985/job/95626278831

3. Change the compiler flags only when building the GCS-related components

This is the approach implemented in the current PR.

diff --git a/cpp/src/arrow/CMakeLists.txt b/cpp/src/arrow/CMakeLists.txt
index 2569b9bcd4..39b3bb5ac1 100644
--- a/cpp/src/arrow/CMakeLists.txt+++ b/cpp/src/arrow/CMakeLists.txt@@ -983,6 +983,13 @@ if(ARROW_FILESYSTEM)
"-Wno-documentation;-Wno-documentation-deprecated-sync"
)
endif()
+ # Workaround deprecated Abseil APIs used by google-cloud-cpp on macOS+ # https://github.com/apache/arrow/issues/50868+ if(APPLE)+ set_property(SOURCE filesystem/gcsfs.cc filesystem/gcsfs_internal.cc+ APPEND+ PROPERTY COMPILE_OPTIONS "-Wno-error=deprecated-declarations")+ endif()
endif()
if(ARROW_HDFS)
list(APPEND ARROW_FILESYSTEM_SRCS filesystem/hdfs.cc)

[hiroyuki-sato]

rebased for re-run CI.

[hiroyuki-sato]

Tes Ruby failed re-applied skip red-arrow-flight test on macOS.

[kou]

+1

[conbench-apache-arrow]

After merging your PR, Conbench analyzed the 3 benchmarking runs that have been run so far on merge-commit 6b429a0.

There were no benchmark performance regressions. 🎉

The full Conbench report has more details. It also includes information about 4 possible false positives for unstable benchmarks that are known to sometimes produce them.