unix: remove Go 1.12 compatibility on darwin

Go 1.12 was released more than 3 years ago. Dropping support for it will
simplify generating the wrappers needed for Getdirentries
implementation.

Change-Id: If24bf6ff9076fb4e281948c67bac87744df98d7a
Reviewed-on: https://go-review.googlesource.com/c/sys/+/430176
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
diff --git a/unix/mkall.sh b/unix/mkall.sh
index 3b2335d..1b2b424 100755
--- a/unix/mkall.sh
+++ b/unix/mkall.sh
@@ -214,11 +214,6 @@
 			if [ "$GOOSARCH" == "aix_ppc64" ]; then
 				# aix/ppc64 script generates files instead of writing to stdin.
 				echo "$mksyscall -tags $GOOS,$GOARCH $syscall_goos $GOOSARCH_in && gofmt -w zsyscall_$GOOSARCH.go && gofmt -w zsyscall_"$GOOSARCH"_gccgo.go && gofmt -w zsyscall_"$GOOSARCH"_gc.go " ;
-			elif [ "$GOOS" == "darwin" ]; then
-			        # 1.12 and later, syscalls via libSystem
-				echo "$mksyscall -tags $GOOS,$GOARCH,go1.12 $syscall_goos $GOOSARCH_in |gofmt >zsyscall_$GOOSARCH.go";
-				# 1.13 and later, syscalls via libSystem (including syscallPtr)
-				echo "$mksyscall -tags $GOOS,$GOARCH,go1.13 syscall_darwin.1_13.go |gofmt >zsyscall_$GOOSARCH.1_13.go";
 			elif [ "$GOOS" == "illumos" ]; then
 			        # illumos code generation requires a --illumos switch
 			        echo "$mksyscall -illumos -tags illumos,$GOARCH syscall_illumos.go |gofmt > zsyscall_illumos_$GOARCH.go";
diff --git a/unix/mkasm.go b/unix/mkasm.go
index e277521..f73d032 100644
--- a/unix/mkasm.go
+++ b/unix/mkasm.go
@@ -31,7 +31,7 @@
 	}
 }
 
-func generateASMFile(arch string, inFileNames []string, outFileName, buildTags string) map[string]bool {
+func generateASMFile(arch string, inFileNames []string, outFileName string) map[string]bool {
 	trampolines := map[string]bool{}
 	var orderedTrampolines []string
 	for _, inFileName := range inFileNames {
@@ -59,11 +59,6 @@
 	fmt.Fprintf(&out, "// go run mkasm.go %s\n", strings.Join(os.Args[1:], " "))
 	fmt.Fprintf(&out, "// Code generated by the command above; DO NOT EDIT.\n")
 	fmt.Fprintf(&out, "\n")
-	if buildTags != "" {
-		fmt.Fprintf(&out, "//go:build %s\n", buildTags)
-		fmt.Fprintf(&out, "// +build %s\n", buildTags)
-		fmt.Fprintf(&out, "\n")
-	}
 	fmt.Fprintf(&out, "#include \"textflag.h\"\n")
 	for _, fn := range orderedTrampolines {
 		fmt.Fprintf(&out, "\nTEXT %s_trampoline<>(SB),NOSPLIT,$0-0\n", fn)
@@ -121,7 +116,6 @@
 	}
 	goos, arch := os.Args[1], os.Args[2]
 
-	buildTags := ""
 	syscallFilename := fmt.Sprintf("syscall_%s.go", goos)
 	syscallArchFilename := fmt.Sprintf("syscall_%s_%s.go", goos, arch)
 	zsyscallArchFilename := fmt.Sprintf("zsyscall_%s_%s.go", goos, arch)
@@ -133,25 +127,9 @@
 		zsyscallArchFilename,
 	}
 
+	trampolines := generateASMFile(arch, inFileNames, zsyscallASMFileName)
+
 	if goos == "darwin" {
-		buildTags = "go1.12"
+		writeDarwinTest(trampolines, fmt.Sprintf("darwin_%s_test.go", arch), arch)
 	}
-	trampolines := generateASMFile(arch, inFileNames, zsyscallASMFileName, buildTags)
-
-	if goos != "darwin" {
-		return
-	}
-
-	inFileNames = []string{
-		"syscall_darwin.1_13.go",
-		fmt.Sprintf("zsyscall_darwin_%s.1_13.go", arch),
-	}
-	trampolines2 := generateASMFile(arch, inFileNames, fmt.Sprintf("zsyscall_darwin_%s.1_13.s", arch), "go1.13")
-
-	// merge trampolines
-	for trampoline := range trampolines2 {
-		trampolines[trampoline] = true
-	}
-
-	writeDarwinTest(trampolines, fmt.Sprintf("darwin_%s_test.go", arch), arch)
 }
diff --git a/unix/syscall_darwin.1_12.go b/unix/syscall_darwin.1_12.go
deleted file mode 100644
index b009860..0000000
--- a/unix/syscall_darwin.1_12.go
+++ /dev/null
@@ -1,32 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build darwin && go1.12 && !go1.13
-// +build darwin,go1.12,!go1.13
-
-package unix
-
-import (
-	"unsafe"
-)
-
-const _SYS_GETDIRENTRIES64 = 344
-
-func Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error) {
-	// To implement this using libSystem we'd need syscall_syscallPtr for
-	// fdopendir. However, syscallPtr was only added in Go 1.13, so we fall
-	// back to raw syscalls for this func on Go 1.12.
-	var p unsafe.Pointer
-	if len(buf) > 0 {
-		p = unsafe.Pointer(&buf[0])
-	} else {
-		p = unsafe.Pointer(&_zero)
-	}
-	r0, _, e1 := Syscall6(_SYS_GETDIRENTRIES64, uintptr(fd), uintptr(p), uintptr(len(buf)), uintptr(unsafe.Pointer(basep)), 0, 0)
-	n = int(r0)
-	if e1 != 0 {
-		return n, errnoErr(e1)
-	}
-	return n, nil
-}
diff --git a/unix/syscall_darwin.1_13.go b/unix/syscall_darwin.1_13.go
deleted file mode 100644
index 1259f6d..0000000
--- a/unix/syscall_darwin.1_13.go
+++ /dev/null
@@ -1,100 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-//go:build darwin && go1.13
-// +build darwin,go1.13
-
-package unix
-
-import "unsafe"
-
-//sys	closedir(dir uintptr) (err error)
-//sys	readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno)
-
-func fdopendir(fd int) (dir uintptr, err error) {
-	r0, _, e1 := syscall_syscallPtr(libc_fdopendir_trampoline_addr, uintptr(fd), 0, 0)
-	dir = uintptr(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-var libc_fdopendir_trampoline_addr uintptr
-
-//go:cgo_import_dynamic libc_fdopendir fdopendir "/usr/lib/libSystem.B.dylib"
-
-func Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error) {
-	// Simulate Getdirentries using fdopendir/readdir_r/closedir.
-	// We store the number of entries to skip in the seek
-	// offset of fd. See issue #31368.
-	// It's not the full required semantics, but should handle the case
-	// of calling Getdirentries or ReadDirent repeatedly.
-	// It won't handle assigning the results of lseek to *basep, or handle
-	// the directory being edited underfoot.
-	skip, err := Seek(fd, 0, 1 /* SEEK_CUR */)
-	if err != nil {
-		return 0, err
-	}
-
-	// We need to duplicate the incoming file descriptor
-	// because the caller expects to retain control of it, but
-	// fdopendir expects to take control of its argument.
-	// Just Dup'ing the file descriptor is not enough, as the
-	// result shares underlying state. Use Openat to make a really
-	// new file descriptor referring to the same directory.
-	fd2, err := Openat(fd, ".", O_RDONLY, 0)
-	if err != nil {
-		return 0, err
-	}
-	d, err := fdopendir(fd2)
-	if err != nil {
-		Close(fd2)
-		return 0, err
-	}
-	defer closedir(d)
-
-	var cnt int64
-	for {
-		var entry Dirent
-		var entryp *Dirent
-		e := readdir_r(d, &entry, &entryp)
-		if e != 0 {
-			return n, errnoErr(e)
-		}
-		if entryp == nil {
-			break
-		}
-		if skip > 0 {
-			skip--
-			cnt++
-			continue
-		}
-
-		reclen := int(entry.Reclen)
-		if reclen > len(buf) {
-			// Not enough room. Return for now.
-			// The counter will let us know where we should start up again.
-			// Note: this strategy for suspending in the middle and
-			// restarting is O(n^2) in the length of the directory. Oh well.
-			break
-		}
-
-		// Copy entry into return buffer.
-		s := unsafe.Slice((*byte)(unsafe.Pointer(&entry)), reclen)
-		copy(buf, s)
-
-		buf = buf[reclen:]
-		n += reclen
-		cnt++
-	}
-	// Set the seek offset of the input fd to record
-	// how many files we've already returned.
-	_, err = Seek(fd, cnt, 0 /* SEEK_SET */)
-	if err != nil {
-		return n, err
-	}
-
-	return n, nil
-}
diff --git a/unix/syscall_darwin.go b/unix/syscall_darwin.go
index 4f87f16..1f63382 100644
--- a/unix/syscall_darwin.go
+++ b/unix/syscall_darwin.go
@@ -19,6 +19,96 @@
 	"unsafe"
 )
 
+//sys	closedir(dir uintptr) (err error)
+//sys	readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno)
+
+func fdopendir(fd int) (dir uintptr, err error) {
+	r0, _, e1 := syscall_syscallPtr(libc_fdopendir_trampoline_addr, uintptr(fd), 0, 0)
+	dir = uintptr(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_fdopendir_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_fdopendir fdopendir "/usr/lib/libSystem.B.dylib"
+
+func Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error) {
+	// Simulate Getdirentries using fdopendir/readdir_r/closedir.
+	// We store the number of entries to skip in the seek
+	// offset of fd. See issue #31368.
+	// It's not the full required semantics, but should handle the case
+	// of calling Getdirentries or ReadDirent repeatedly.
+	// It won't handle assigning the results of lseek to *basep, or handle
+	// the directory being edited underfoot.
+	skip, err := Seek(fd, 0, 1 /* SEEK_CUR */)
+	if err != nil {
+		return 0, err
+	}
+
+	// We need to duplicate the incoming file descriptor
+	// because the caller expects to retain control of it, but
+	// fdopendir expects to take control of its argument.
+	// Just Dup'ing the file descriptor is not enough, as the
+	// result shares underlying state. Use Openat to make a really
+	// new file descriptor referring to the same directory.
+	fd2, err := Openat(fd, ".", O_RDONLY, 0)
+	if err != nil {
+		return 0, err
+	}
+	d, err := fdopendir(fd2)
+	if err != nil {
+		Close(fd2)
+		return 0, err
+	}
+	defer closedir(d)
+
+	var cnt int64
+	for {
+		var entry Dirent
+		var entryp *Dirent
+		e := readdir_r(d, &entry, &entryp)
+		if e != 0 {
+			return n, errnoErr(e)
+		}
+		if entryp == nil {
+			break
+		}
+		if skip > 0 {
+			skip--
+			cnt++
+			continue
+		}
+
+		reclen := int(entry.Reclen)
+		if reclen > len(buf) {
+			// Not enough room. Return for now.
+			// The counter will let us know where we should start up again.
+			// Note: this strategy for suspending in the middle and
+			// restarting is O(n^2) in the length of the directory. Oh well.
+			break
+		}
+
+		// Copy entry into return buffer.
+		s := unsafe.Slice((*byte)(unsafe.Pointer(&entry)), reclen)
+		copy(buf, s)
+
+		buf = buf[reclen:]
+		n += reclen
+		cnt++
+	}
+	// Set the seek offset of the input fd to record
+	// how many files we've already returned.
+	_, err = Seek(fd, cnt, 0 /* SEEK_SET */)
+	if err != nil {
+		return n, err
+	}
+
+	return n, nil
+}
+
 // SockaddrDatalink implements the Sockaddr interface for AF_LINK type sockets.
 type SockaddrDatalink struct {
 	Len    uint8
diff --git a/unix/zsyscall_darwin_amd64.1_13.go b/unix/zsyscall_darwin_amd64.1_13.go
deleted file mode 100644
index a06eb09..0000000
--- a/unix/zsyscall_darwin_amd64.1_13.go
+++ /dev/null
@@ -1,40 +0,0 @@
-// go run mksyscall.go -tags darwin,amd64,go1.13 syscall_darwin.1_13.go
-// Code generated by the command above; see README.md. DO NOT EDIT.
-
-//go:build darwin && amd64 && go1.13
-// +build darwin,amd64,go1.13
-
-package unix
-
-import (
-	"syscall"
-	"unsafe"
-)
-
-var _ syscall.Errno
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func closedir(dir uintptr) (err error) {
-	_, _, e1 := syscall_syscall(libc_closedir_trampoline_addr, uintptr(dir), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-var libc_closedir_trampoline_addr uintptr
-
-//go:cgo_import_dynamic libc_closedir closedir "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno) {
-	r0, _, _ := syscall_syscall(libc_readdir_r_trampoline_addr, uintptr(dir), uintptr(unsafe.Pointer(entry)), uintptr(unsafe.Pointer(result)))
-	res = Errno(r0)
-	return
-}
-
-var libc_readdir_r_trampoline_addr uintptr
-
-//go:cgo_import_dynamic libc_readdir_r readdir_r "/usr/lib/libSystem.B.dylib"
diff --git a/unix/zsyscall_darwin_amd64.1_13.s b/unix/zsyscall_darwin_amd64.1_13.s
deleted file mode 100644
index f5bb40e..0000000
--- a/unix/zsyscall_darwin_amd64.1_13.s
+++ /dev/null
@@ -1,25 +0,0 @@
-// go run mkasm.go darwin amd64
-// Code generated by the command above; DO NOT EDIT.
-
-//go:build go1.13
-// +build go1.13
-
-#include "textflag.h"
-
-TEXT libc_fdopendir_trampoline<>(SB),NOSPLIT,$0-0
-	JMP	libc_fdopendir(SB)
-
-GLOBL	·libc_fdopendir_trampoline_addr(SB), RODATA, $8
-DATA	·libc_fdopendir_trampoline_addr(SB)/8, $libc_fdopendir_trampoline<>(SB)
-
-TEXT libc_closedir_trampoline<>(SB),NOSPLIT,$0-0
-	JMP	libc_closedir(SB)
-
-GLOBL	·libc_closedir_trampoline_addr(SB), RODATA, $8
-DATA	·libc_closedir_trampoline_addr(SB)/8, $libc_closedir_trampoline<>(SB)
-
-TEXT libc_readdir_r_trampoline<>(SB),NOSPLIT,$0-0
-	JMP	libc_readdir_r(SB)
-
-GLOBL	·libc_readdir_r_trampoline_addr(SB), RODATA, $8
-DATA	·libc_readdir_r_trampoline_addr(SB)/8, $libc_readdir_r_trampoline<>(SB)
diff --git a/unix/zsyscall_darwin_amd64.go b/unix/zsyscall_darwin_amd64.go
index 467deed..c2461c4 100644
--- a/unix/zsyscall_darwin_amd64.go
+++ b/unix/zsyscall_darwin_amd64.go
@@ -1,8 +1,8 @@
-// go run mksyscall.go -tags darwin,amd64,go1.12 syscall_bsd.go syscall_darwin.go syscall_darwin_amd64.go
+// go run mksyscall.go -tags darwin,amd64 syscall_bsd.go syscall_darwin.go syscall_darwin_amd64.go
 // Code generated by the command above; see README.md. DO NOT EDIT.
 
-//go:build darwin && amd64 && go1.12
-// +build darwin,amd64,go1.12
+//go:build darwin && amd64
+// +build darwin,amd64
 
 package unix
 
@@ -463,6 +463,32 @@
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func closedir(dir uintptr) (err error) {
+	_, _, e1 := syscall_syscall(libc_closedir_trampoline_addr, uintptr(dir), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_closedir_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_closedir closedir "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno) {
+	r0, _, _ := syscall_syscall(libc_readdir_r_trampoline_addr, uintptr(dir), uintptr(unsafe.Pointer(entry)), uintptr(unsafe.Pointer(result)))
+	res = Errno(r0)
+	return
+}
+
+var libc_readdir_r_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_readdir_r readdir_r "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func pipe(p *[2]int32) (err error) {
 	_, _, e1 := syscall_rawSyscall(libc_pipe_trampoline_addr, uintptr(unsafe.Pointer(p)), 0, 0)
 	if e1 != 0 {
diff --git a/unix/zsyscall_darwin_amd64.s b/unix/zsyscall_darwin_amd64.s
index b41467a..95fe4c0 100644
--- a/unix/zsyscall_darwin_amd64.s
+++ b/unix/zsyscall_darwin_amd64.s
@@ -1,11 +1,14 @@
 // go run mkasm.go darwin amd64
 // Code generated by the command above; DO NOT EDIT.
 
-//go:build go1.12
-// +build go1.12
-
 #include "textflag.h"
 
+TEXT libc_fdopendir_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_fdopendir(SB)
+
+GLOBL	·libc_fdopendir_trampoline_addr(SB), RODATA, $8
+DATA	·libc_fdopendir_trampoline_addr(SB)/8, $libc_fdopendir_trampoline<>(SB)
+
 TEXT libc_getgroups_trampoline<>(SB),NOSPLIT,$0-0
 	JMP	libc_getgroups(SB)
 
@@ -174,6 +177,18 @@
 GLOBL	·libc_munlockall_trampoline_addr(SB), RODATA, $8
 DATA	·libc_munlockall_trampoline_addr(SB)/8, $libc_munlockall_trampoline<>(SB)
 
+TEXT libc_closedir_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_closedir(SB)
+
+GLOBL	·libc_closedir_trampoline_addr(SB), RODATA, $8
+DATA	·libc_closedir_trampoline_addr(SB)/8, $libc_closedir_trampoline<>(SB)
+
+TEXT libc_readdir_r_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_readdir_r(SB)
+
+GLOBL	·libc_readdir_r_trampoline_addr(SB), RODATA, $8
+DATA	·libc_readdir_r_trampoline_addr(SB)/8, $libc_readdir_r_trampoline<>(SB)
+
 TEXT libc_pipe_trampoline<>(SB),NOSPLIT,$0-0
 	JMP	libc_pipe(SB)
 
diff --git a/unix/zsyscall_darwin_arm64.1_13.go b/unix/zsyscall_darwin_arm64.1_13.go
deleted file mode 100644
index cec595d..0000000
--- a/unix/zsyscall_darwin_arm64.1_13.go
+++ /dev/null
@@ -1,40 +0,0 @@
-// go run mksyscall.go -tags darwin,arm64,go1.13 syscall_darwin.1_13.go
-// Code generated by the command above; see README.md. DO NOT EDIT.
-
-//go:build darwin && arm64 && go1.13
-// +build darwin,arm64,go1.13
-
-package unix
-
-import (
-	"syscall"
-	"unsafe"
-)
-
-var _ syscall.Errno
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func closedir(dir uintptr) (err error) {
-	_, _, e1 := syscall_syscall(libc_closedir_trampoline_addr, uintptr(dir), 0, 0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-var libc_closedir_trampoline_addr uintptr
-
-//go:cgo_import_dynamic libc_closedir closedir "/usr/lib/libSystem.B.dylib"
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
-func readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno) {
-	r0, _, _ := syscall_syscall(libc_readdir_r_trampoline_addr, uintptr(dir), uintptr(unsafe.Pointer(entry)), uintptr(unsafe.Pointer(result)))
-	res = Errno(r0)
-	return
-}
-
-var libc_readdir_r_trampoline_addr uintptr
-
-//go:cgo_import_dynamic libc_readdir_r readdir_r "/usr/lib/libSystem.B.dylib"
diff --git a/unix/zsyscall_darwin_arm64.1_13.s b/unix/zsyscall_darwin_arm64.1_13.s
deleted file mode 100644
index 0c3f76b..0000000
--- a/unix/zsyscall_darwin_arm64.1_13.s
+++ /dev/null
@@ -1,25 +0,0 @@
-// go run mkasm.go darwin arm64
-// Code generated by the command above; DO NOT EDIT.
-
-//go:build go1.13
-// +build go1.13
-
-#include "textflag.h"
-
-TEXT libc_fdopendir_trampoline<>(SB),NOSPLIT,$0-0
-	JMP	libc_fdopendir(SB)
-
-GLOBL	·libc_fdopendir_trampoline_addr(SB), RODATA, $8
-DATA	·libc_fdopendir_trampoline_addr(SB)/8, $libc_fdopendir_trampoline<>(SB)
-
-TEXT libc_closedir_trampoline<>(SB),NOSPLIT,$0-0
-	JMP	libc_closedir(SB)
-
-GLOBL	·libc_closedir_trampoline_addr(SB), RODATA, $8
-DATA	·libc_closedir_trampoline_addr(SB)/8, $libc_closedir_trampoline<>(SB)
-
-TEXT libc_readdir_r_trampoline<>(SB),NOSPLIT,$0-0
-	JMP	libc_readdir_r(SB)
-
-GLOBL	·libc_readdir_r_trampoline_addr(SB), RODATA, $8
-DATA	·libc_readdir_r_trampoline_addr(SB)/8, $libc_readdir_r_trampoline<>(SB)
diff --git a/unix/zsyscall_darwin_arm64.go b/unix/zsyscall_darwin_arm64.go
index 35938d3..26a0fdc 100644
--- a/unix/zsyscall_darwin_arm64.go
+++ b/unix/zsyscall_darwin_arm64.go
@@ -1,8 +1,8 @@
-// go run mksyscall.go -tags darwin,arm64,go1.12 syscall_bsd.go syscall_darwin.go syscall_darwin_arm64.go
+// go run mksyscall.go -tags darwin,arm64 syscall_bsd.go syscall_darwin.go syscall_darwin_arm64.go
 // Code generated by the command above; see README.md. DO NOT EDIT.
 
-//go:build darwin && arm64 && go1.12
-// +build darwin,arm64,go1.12
+//go:build darwin && arm64
+// +build darwin,arm64
 
 package unix
 
@@ -463,6 +463,32 @@
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func closedir(dir uintptr) (err error) {
+	_, _, e1 := syscall_syscall(libc_closedir_trampoline_addr, uintptr(dir), 0, 0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+var libc_closedir_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_closedir closedir "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno) {
+	r0, _, _ := syscall_syscall(libc_readdir_r_trampoline_addr, uintptr(dir), uintptr(unsafe.Pointer(entry)), uintptr(unsafe.Pointer(result)))
+	res = Errno(r0)
+	return
+}
+
+var libc_readdir_r_trampoline_addr uintptr
+
+//go:cgo_import_dynamic libc_readdir_r readdir_r "/usr/lib/libSystem.B.dylib"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func pipe(p *[2]int32) (err error) {
 	_, _, e1 := syscall_rawSyscall(libc_pipe_trampoline_addr, uintptr(unsafe.Pointer(p)), 0, 0)
 	if e1 != 0 {
diff --git a/unix/zsyscall_darwin_arm64.s b/unix/zsyscall_darwin_arm64.s
index e1f9204..efa5b4c 100644
--- a/unix/zsyscall_darwin_arm64.s
+++ b/unix/zsyscall_darwin_arm64.s
@@ -1,11 +1,14 @@
 // go run mkasm.go darwin arm64
 // Code generated by the command above; DO NOT EDIT.
 
-//go:build go1.12
-// +build go1.12
-
 #include "textflag.h"
 
+TEXT libc_fdopendir_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_fdopendir(SB)
+
+GLOBL	·libc_fdopendir_trampoline_addr(SB), RODATA, $8
+DATA	·libc_fdopendir_trampoline_addr(SB)/8, $libc_fdopendir_trampoline<>(SB)
+
 TEXT libc_getgroups_trampoline<>(SB),NOSPLIT,$0-0
 	JMP	libc_getgroups(SB)
 
@@ -174,6 +177,18 @@
 GLOBL	·libc_munlockall_trampoline_addr(SB), RODATA, $8
 DATA	·libc_munlockall_trampoline_addr(SB)/8, $libc_munlockall_trampoline<>(SB)
 
+TEXT libc_closedir_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_closedir(SB)
+
+GLOBL	·libc_closedir_trampoline_addr(SB), RODATA, $8
+DATA	·libc_closedir_trampoline_addr(SB)/8, $libc_closedir_trampoline<>(SB)
+
+TEXT libc_readdir_r_trampoline<>(SB),NOSPLIT,$0-0
+	JMP	libc_readdir_r(SB)
+
+GLOBL	·libc_readdir_r_trampoline_addr(SB), RODATA, $8
+DATA	·libc_readdir_r_trampoline_addr(SB)/8, $libc_readdir_r_trampoline<>(SB)
+
 TEXT libc_pipe_trampoline<>(SB),NOSPLIT,$0-0
 	JMP	libc_pipe(SB)