Describe the bug, including details regarding any error messages, version, and platform.
Update:
Diagnostic CI run confirms a single upstream root cause for all failures listed here.
Filed upstream as GCC #125312 (diagnosis: #49961). Fix in upstream MSYS2 msys2/MINGW-packages#29502
Umbrella issue for follow-up to closed #49930/merged PR #49931 (a temporary workaround!).
The MSYS gcc 15.2 -> 16.1 update post 2026 April 30 broke the MINGW64 MinGW job. #49931 pins gcc-libs to 15.2 to mask/workaround it. This issue tracks the actual fixes so the pin step can be reverted (later with #49945).
Sub-issues will be opened for individual failures as triage progresses.
First failure on main:
The following tests FAILED:
41 - arrow-async-utility-test (Exit code 0xc0000374) arrow-tests unittest
62 - arrow-dataset-dataset-writer-test (SEGFAULT) arrow_dataset unittest
65 - arrow-dataset-file-test (Failed) arrow_dataset unittest
Error: Process completed with exit code 8.
Another CI run from PR 49462
Empirical isolation (PR #49931 commit fb4d7a0, pins removed, MinIO bumped) - MINGW64 CI run:
The following tests FAILED:
41 - arrow-async-utility-test (Exit code 0xc0000374) arrow-tests unittest
44 - arrow-threading-utility-test (Timeout) arrow-tests unittest
62 - arrow-dataset-dataset-writer-test (Failed) arrow_dataset unittest
65 - arrow-dataset-file-test (Failed) arrow_dataset unittest
76 - arrow-s3fs-test (Timeout) arrow-tests filesystem unittest
CLANG64 in the same run: 100% tests passed. Confirmed gcc-16 is the trigger (not the gcc-libs cascade or aws-sdk-cpp/MinIO behavior).
Per-test status:
Root cause: GCC 125312, diagnosis: #49961, verifying CI run: https://github.com/apache/arrow/actions/runs/25916033144/job/76180927231#step:14:494
(fixed)
This issue closes when
Component(s)
Continuous Integration, C++
Describe the bug, including details regarding any error messages, version, and platform.
Update:
Diagnostic CI run confirms a single upstream root cause for all failures listed here.
Filed upstream as GCC #125312 (diagnosis: #49961). Fix in upstream MSYS2 msys2/MINGW-packages#29502
Umbrella issue for follow-up to closed #49930/merged PR #49931 (a temporary workaround!).
The MSYS
gcc 15.2 -> 16.1update post 2026 April 30 broke the MINGW64 MinGW job. #49931 pinsgcc-libsto 15.2 to mask/workaround it. This issue tracks the actual fixes so the pin step can be reverted (later with #49945).Sub-issues will be opened for individual failures as triage progresses.
First failure on main:
Another CI run from PR 49462
Empirical isolation (PR #49931 commit
fb4d7a0, pins removed, MinIO bumped) - MINGW64 CI run:CLANG64 in the same run:
100% tests passed. Confirmed gcc-16 is the trigger (not the gcc-libs cascade or aws-sdk-cpp/MinIO behavior).Per-test status:
Root cause: GCC 125312, diagnosis: #49961, verifying CI run: https://github.com/apache/arrow/actions/runs/25916033144/job/76180927231#step:14:494
arrow-async-utility-testwas: Heap corruption0xc0000374inPushGenerator.Stress(sometimes passed - on 2nd attempt CI log there, failed 3 times there)arrow-threading-utility-testwas:SegFaultlog1 orTimeout 300.00 seclog2 (race signature)arrow-dataset-dataset-writer-testwas:std::bad_weak_ptrinBatchWriteConcurrentarrow-dataset-file-testwas:SegFault, same race asarrow-dataset-dataset-writer-test(intermittent)
arrow-acero-hash-join-node-testwas:HashJoin.Random(parallel = true) doesn'temit the expected number of batches. Ex. CI failed logs here1 and here2(Update: NOT a distinct root cause)
arrow-flight-testwas: gRPC'smemory_quota.cc:280CHECKfailure inLargeBatchtests, also atmemory_quota.cc:281, byte mismatches vary across retries . See in Example log1, log2 and new log3 - race from gRPC'sshared_ptrand buggy__exchange_and_addinlibstdc++-6.dll. Needs themingw-w64-x86_64-gcc-libs 15.2pin (or better the MSYS2 rebuild, see gcc: Fix atomicity of reference counters instd::{shared,weak}_ptrmsys2/MINGW-packages#29502) asgRPC.dllwas pre-compiled by MSYS2 against the broken DLL-- (earlier) original[C++] Linux Flight/FlightSQL test randomly segfaults after gRPC version bump #49767 describes non-MinGW Windows (MSVC/ODBC) that might still be a separate gRPC issue (bump in GH-48926: [C++] Upgrade Abseil/Protobuf/GRPC/Google-Cloud-CPP bundled versions #48964).
(fixed)
arrow-json-test:MultipleChunksParallelcrash - Fixed by GH-49272: [C++][CI] Fix intermittent segfault in arrow-json-test with MinGW #49462arrow-s3fs-test:_fut.Wait()timeout inGetFileInfoGeneratorStress. Observed failing and passing. Same thread-pool class as others; the SDK-sideMissingContentMD5mode was separately resolved by GH-49930: [CI][C++] Pin MinGW MSYS2 packages to unblock CI #49931's MinIO bump.This issue closes when
std::{shared,weak}_ptrmsys2/MINGW-packages#29502 - merged 2026 May 15! )- name: Pin MSYS2 packages)Component(s)
Continuous Integration, C++