ppc64le offload build broken by 8437b7f5584765ad4f7885500647657714930fbb

[tstellar]

@jhuber6 This commit 8437b7f ( #131205) broke the build on ppc64le. You can reproduce by configuring with:

cmake -G Ninja -B build -S llvm -DCMAKE_BUILD_TYPE=Release -DLLVM_TARGETS_TO_BUILD=Native -DLLVM_ENABLE_PROJECTS=clang -DLLVM_ENABLE_RUNTIMES="offload;openmp;compiler-rt" -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_C_COMPILER=clang

And running:

ninja -C build runtimes

See attached build logs for details. Note we aren't seeing the same failures on configurations where llvm is built with -DPPC_LINUX_DEFAULT_IEEELONGDOUBLE:BOOL=ON.

[tstellar]

build.log.txt

[llvmbot]

@llvm/issue-subscribers-offload

Author: Tom Stellard (tstellar)

@jhuber6 This commit broke the build on ppc64le. You can reproduce by configuring with: ``` cmake -G Ninja -B build -S llvm -DCMAKE_BUILD_TYPE=Release -DLLVM_TARGETS_TO_BUILD=Native -DLLVM_ENABLE_PROJECTS=clang -DLLVM_ENABLE_RUNTIMES="offload;openmp;compiler-rt" -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_C_COMPILER=clang ```

And running:

ninja -C build runtimes

See attached build logs for details. Note we aren't seeing the same failures on configurations where llvm is built with -DPPC_LINUX_DEFAULT_IEEELONGDOUBLE:BOOL=ON.

[jhuber6]

Can you link the PR more easily? I'm going to assume that there's some missing ifdef for this weird PPC float.

[llvmbot]

@llvm/issue-subscribers-backend-powerpc

Author: Tom Stellard (tstellar)

@jhuber6 This commit ( https://github.com//pull/131205) broke the build on ppc64le. You can reproduce by configuring with: ``` cmake -G Ninja -B build -S llvm -DCMAKE_BUILD_TYPE=Release -DLLVM_TARGETS_TO_BUILD=Native -DLLVM_ENABLE_PROJECTS=clang -DLLVM_ENABLE_RUNTIMES="offload;openmp;compiler-rt" -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_C_COMPILER=clang ```

And running:

ninja -C build runtimes

See attached build logs for details. Note we aren't seeing the same failures on configurations where llvm is built with -DPPC_LINUX_DEFAULT_IEEELONGDOUBLE:BOOL=ON.

[jhuber6]

This log is confusing me, one of the errors says this, but it was fixed ages ago. Is this a really old build?

/root/llvm-project/llvm/cmake/modules/../../../libc/src/string/memory_utils/inline_memset.h:34:2: error: "Unsupported architecture"
   34 | #error "Unsupported architecture"

[jhuber6]

My best guess is that we don't handle PPC's doubledouble format for long double.

[tstellar]

I'm building with 8437b7f.

[tstellar]

Here is a more recent build log (link is only good for 2 weeks): https://download.copr.fedorainfracloud.org/results/@fedora-llvm-team/llvm-snapshots-big-merge-20250421/centos-stream-9-ppc64le/08948252-llvm/builder-live.log.gz