### ARM64 {#arm64}

<!-- go.dev/issue/60905, CL 559555 -->
Go 1.23 introduces a new `GOARM64` environment variable, which specifies the minimum target version of the ARM64 architecture at compile time. Allowed values are `v8.{0-9}` and `v9.{0-5}`. This may be followed by an option specifying extensions implemented by target hardware. Valid options are `,lse` and `,crypto`.

The `GOARM64` environment variable defaults to `v8.0`.

### RISC-V {#riscv}

	GOARM64
		For GOARCH=arm64, the ARM64 architecture for which to compile.
		Valid values are v8.0 (default), v8.{1-9}, v9.{0-5}.
		The value can be followed by an option specifying extensions implemented by target hardware.
		Valid options are ,lse and ,crypto.
		Note that some extensions are enabled by default starting from a certain GOARM64 version;

//	GOARM64
//		For GOARCH=arm64, the ARM64 architecture for which to compile.
//		Valid values are v8.0 (default), v8.{1-9}, v9.{0-5}.
//		The value can be followed by an option specifying extensions implemented by target hardware.
//		Valid options are ,lse and ,crypto.
//		Note that some extensions are enabled by default starting from a certain GOARM64 version;

	makeAtomicGuardedIntrinsicARM64 := func(op0, op1 ssa.Op, typ types.Kind, emit atomicOpEmitter) intrinsicBuilder {

		return func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value {
			if buildcfg.GOARM64.LSE {
				emit(s, n, args, op1, typ)
			} else {
				// Target Atomic feature is identified by dynamic detection
				addr := s.entryNewValue1A(ssa.OpAddr, types.Types[types.TBOOL].PtrTo(), ir.Syms.ARM64HasATOMICS, s.sb)