}
		if err == _EAGAIN {
			print("runtime: mmap: too much locked memory (check 'ulimit -l').\n")
			exit(2)
		}
		return nil
	}
	return p
}

func sysUnusedOS(v unsafe.Pointer, n uintptr) {
	madvise(v, n, _MADV_DONTNEED)
}

func sysUsedOS(v unsafe.Pointer, n uintptr) {
}

func sysHugePageOS(v unsafe.Pointer, n uintptr) {
}

func sysNoHugePageOS(v unsafe.Pointer, n uintptr) {
}

//
//go:noescape
func write1(fd uintptr, p unsafe.Pointer, n int32) int32

//go:noescape
func open(name *byte, mode, perm int32) int32

// return value is only set on linux to be used in osinit().
func madvise(addr unsafe.Pointer, n uintptr, flags int32) int32

// exitThread terminates the current thread, writing *wait = freeMStack when
// the stack is safe to reclaim.
//
//go:noescape
func exitThread(wait *atomic.Uint32)

		println("syscall munmap failed: ", hex(err))
		throw("syscall munmap")
	}
}

//go:nosplit
func madvise(addr unsafe.Pointer, n uintptr, flags int32) {
	r, err := syscall3(&libc_madvise, uintptr(addr), uintptr(n), uintptr(flags))
	if int32(r) == -1 {
		println("syscall madvise failed: ", hex(err))
		throw("syscall madvise")
	}
}

func sigaction1(sig, new, old uintptr)

//go:nosplit

	KeepAlive(addr) // Just for consistency. Hopefully addr is not a Go address.
}
func munmap_trampoline()

//go:nosplit
//go:cgo_unsafe_args
func madvise(addr unsafe.Pointer, n uintptr, flags int32) {
	libcCall(unsafe.Pointer(abi.FuncPCABI0(madvise_trampoline)), unsafe.Pointer(&addr))
	KeepAlive(addr) // Just for consistency. Hopefully addr is not a Go address.
}

//sys	Unlinkat(dirfd int, path string, flags int) (err error)
//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
//sys	write(fd int, p []byte) (n int, err error)

//sys	Dup2(oldfd int, newfd int) (err error)
//sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = posix_fadvise64
//sys	Fchown(fd int, uid int, gid int) (err error)
//sys	fstat(fd int, stat *Stat_t) (err error)

// license that can be found in the LICENSE file.

//go:build linux && (ppc64 || ppc64le)

package unix

//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
//sys	Fchown(fd int, uid int, gid int) (err error)
//sys	Fstat(fd int, stat *Stat_t) (err error)

// license that can be found in the LICENSE file.

//go:build sparc64 && linux

package unix

//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
//sys	Fchown(fd int, uid int, gid int) (err error)
//sys	Fstat(fd int, stat *Stat_t) (err error)

// license that can be found in the LICENSE file.

//go:build amd64 && linux

package unix

//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
//sys	Fchown(fd int, uid int, gid int) (err error)
//sys	Fstat(fd int, stat *Stat_t) (err error)

// license that can be found in the LICENSE file.

//go:build arm64 && linux

package unix

import "unsafe"

//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) = SYS_EPOLL_PWAIT
//sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
//sys	Fchown(fd int, uid int, gid int) (err error)
//sys	Fstat(fd int, stat *Stat_t) (err error)

//go:cgo_import_dynamic libc_exit _exit "libc.so"
//go:cgo_import_dynamic libc_getcontext getcontext "libc.so"
//go:cgo_import_dynamic libc_kill kill "libc.so"
//go:cgo_import_dynamic libc_madvise madvise "libc.so"
//go:cgo_import_dynamic libc_malloc malloc "libc.so"
//go:cgo_import_dynamic libc_mmap mmap "libc.so"
//go:cgo_import_dynamic libc_munmap munmap "libc.so"
//go:cgo_import_dynamic libc_open open "libc.so"