[llvm-dev] LLD WASM linker has a deadlock race condition bug

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[llvm-dev] LLD WASM linker has a deadlock race condition bug

Shawn Webb via llvm-dev
Greetings,

I would like to bring attention to this bug report:
https://bugs.llvm.org/show_bug.cgi?id=41508

WebAssembly is getting quite some attention in the 8.0.0 release cycle
of LLVM thanks to the target being promoted to non-experimental.
Consequently the WASM linker code in LLD is getting some more broad testing.

In the Zig frontend I've added --no-threads for now, to work around the bug.

Please let me know if there is more information I can provide to help
diagnose and fix this bug in LLD. The repro case I uploaded in the issue
tracker triggers the deadlock about 1 in 6 times for me.

Regards,
Andrew


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Re: [llvm-dev] LLD WASM linker has a deadlock race condition bug

Shawn Webb via llvm-dev
Hi Andrew,

I replied to you on the bug report thread. A suspicious thing I found in lld/wasm is that it calls parallelForEach from a callback function of parallelForEach, although that function is not reentrant.

On Tue, Apr 16, 2019 at 4:35 PM Andrew Kelley via llvm-dev <[hidden email]> wrote:
Greetings,

I would like to bring attention to this bug report:
https://bugs.llvm.org/show_bug.cgi?id=41508

WebAssembly is getting quite some attention in the 8.0.0 release cycle
of LLVM thanks to the target being promoted to non-experimental.
Consequently the WASM linker code in LLD is getting some more broad testing.

In the Zig frontend I've added --no-threads for now, to work around the bug.

Please let me know if there is more information I can provide to help
diagnose and fix this bug in LLD. The repro case I uploaded in the issue
tracker triggers the deadlock about 1 in 6 times for me.

Regards,
Andrew

_______________________________________________
LLVM Developers mailing list
[hidden email]
https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev

_______________________________________________
LLVM Developers mailing list
[hidden email]
https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev