Constant core::arch::aarch64::_TMFAILURE_NEST

pub const _TMFAILURE_NEST: u64 = 1 << 21; // 0x0000_0000_0020_0000u64

🔬 This is a nightly-only experimental API. (stdsimd #48556)

This is supported on AArch64 only.

由于超出了事务嵌套级别，事务中止了