Hi there,
I got a notification about a build failure on the flang-arm64-windows-msvc buildbot earlier today, I’ve included the original email below.
The commit in question that caused the failure added some new intrinsics, touching some tablegen files, which then caused some tests for unrelated intrinsics to fail: https://github.com/llvm/llvm-project/commit/9ba774566e27b76b9c7c2b2ddd108c14... https://lab.llvm.org/buildbot/#/builders/207/builds/15865
But the buildbot went back to green in https://lab.llvm.org/buildbot/#/builders/207/builds/15869 when another PR changed some other tablegen files in the llvm project. I didn’t revert or commit any fixes in the meantime.
Is there maybe some issue with the build cache and how tablegen files interact with it? Just thought I’d flag this to you anyway.
Many thanks Luke
Begin forwarded message:
From: llvm.buildmaster@lab.llvm.org Subject: ☠ Buildbot (LLVM Buildbot): flang-arm64-windows-msvc - failed test (failure) (main) Date: 9 April 2026 at 16:03:07 GMT+8 To: "Luke Lau" luke@igalia.com, "Nikita Popov" npopov@redhat.com Cc: llvm.buildmaster@lab.llvm.org Reply-To: llvm.buildmaster@lab.llvm.org
The Buildbot has detected a new failure on builder flang-arm64-windows-msvc while building llvm.
Full details are available at: https://lab.llvm.org/buildbot/#/builders/207/builds/15865
Worker for this Build: linaro-armv8-windows-msvc-01 Blamelist: Luke Lau luke@igalia.com, Nikita Popov npopov@redhat.com
BUILD FAILED: failed test (failure)
Step 6 (test-build-unified-tree-check-mlir) failure: test (failure) ******************** TEST 'MLIR :: mlir-runner/test-expand-math-approx.mlir' FAILED ******************** Exit Code: 2
Command Output (stdout):
# RUN: at line 1 c:\users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir-opt.exe C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\llvm-project\mlir\test\mlir-runner\test-expand-math-approx.mlir -pass-pipeline="builtin.module(func.func(math-expand-ops),convert-vector-to-scf,convert-scf-to-cf,convert-vector-to-llvm,convert-to-llvm,reconcile-unrealized-casts)" | c:\users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir-runner.exe -e main -entry-point-result=void -O0 -shared-libs=C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir_c_runner_utils.dll -shared-libs=C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir_runner_utils.dll -shared-libs=C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir_float16_utils.dll | c:\users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\filecheck.exe C:\Users\tcwg\llvm-worker\flang-arm64-windows-ms vc\llvm-project\mlir\test\mlir-runner\test-expand-math-approx.mlir # executed command: 'c:\users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir-opt.exe' 'C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\llvm-project\mlir\test\mlir-runner\test-expand-math-approx.mlir' '-pass-pipeline=builtin.module(func.func(math-expand-ops),convert-vector-to-scf,convert-scf-to-cf,convert-vector-to-llvm,convert-to-llvm,reconcile-unrealized-casts)' # executed command: 'c:\users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir-runner.exe' -e main -entry-point-result=void -O0 '-shared-libs=C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir_c_runner_utils.dll' '-shared-libs=C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir_runner_utils.dll' '-shared-libs=C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir_float16_utils.dll' # .---command stderr------------ # | LLVM ERROR: Cannot select: intrinsic %llvm.aarch64.neon.ushl # | PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug. # | Stack dump: # | 0. Program arguments: c:\users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir-runner.exe -e main -entry-point-result=void -O0 -shared-libs=C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir_c_runner_utils.dll -shared-libs=C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir_runner_utils.dll -shared-libs=C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir_float16_utils.dll # | 1. Running pass 'Function Pass Manager' on module 'LLVMDialectModule'. # | 2. Running pass 'AArch64 Instruction Selection' on function '@"func_roundeven32$vector"' # | Exception Code: 0xC000001D # | #0 0x00007ff674c89e4c mlir::detail::FallbackTypeIDResolver::registerImplicitTypeID(class llvm::StringRef) (c:\users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\mlir-runner.exe+0x309e4c) # | #1 0x00007ffec74aae50 (C:\WINDOWS\System32\ucrtbase.dll+0x7ae50) # | #2 0xa25cfffec74aba5c # `----------------------------- # error: command failed with exit status: 0xc000001d # executed command: 'c:\users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\filecheck.exe' 'C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\llvm-project\mlir\test\mlir-runner\test-expand-math-approx.mlir' # .---command stderr------------ # | FileCheck error: '<stdin>' is empty. # | FileCheck command line: c:\users\tcwg\llvm-worker\flang-arm64-windows-msvc\build\bin\filecheck.exe C:\Users\tcwg\llvm-worker\flang-arm64-windows-msvc\llvm-project\mlir\test\mlir-runner\test-expand-math-approx.mlir # `----------------------------- # error: command failed with exit status: 2
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Sincerely, LLVM Buildbot