detect: Workaround Exynos 9810 bug on aarch64 Android#76
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Samsung Exynos 9810 has a bug that big and little cores have different ISAs. And on older Android (pre-9), the kernel incorrectly reports that features available only on some cores are available on all cores. https://reviews.llvm.org/D114523
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This was referenced Feb 10, 2023
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Samsung Exynos 9810 has a bug that big and little cores have different ISAs. And on older Android (pre-9), the kernel incorrectly reports that features available only on some cores are available on all cores.
See https://reviews.llvm.org/D114523 for details.
Our own run-time detection code has not been released yet and is not a problem, but portable-atomic < 1.1 may have been affected by this issue since rustc 1.69-nightly when is_aarch64_feature_detected supported run-time detection on Android. (rust-lang/stdarch#1351, rust-lang/rust#105784)
A patch on stdarch side: rust-lang/stdarch#1378