syscall: make Exit call runtime.exit

syscall.Exit and runtime.exit do the same thing.
Why duplicate code?

CL 45115 fixed bug where windows runtime.exit was correct,
but syscall.Exit was broken. So CL 45115 fixed windows
syscall.Exit by calling runtime.exit.

Austin suggested that all OSes should do the same, and
this CL implements his idea.

While making changes, I discovered that nacl syscall.Exit
returned error

func Exit(code int) (err error)

and I changed it into

func Exit(code int)

like all other OSes. I assumed it was a mistake and it
is OK to do because cmd/api does not complain about it.

Also I changed plan9 runtime.exit to accept int32 just
like all other OSes do.

Change-Id: I12f6022ad81406566cf9befcc6edc382eebd413b
Reviewed-on: https://go-review.googlesource.com/66170
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: David du Colombier <0intro@gmail.com>

src/runtime/os_plan9.go

@@ -393,7 +393,7 @@ func postnote(pid uint64, msg []byte) int {
 }
 
 //go:nosplit
-func exit(e int) {
+func exit(e int32) {
 	var status []byte
 	if e == 0 {
 		status = emptystatus

src/runtime/runtime.go

@@ -57,3 +57,9 @@ func syscall_Getpagesize() int { return int(physPageSize) }
 
 //go:linkname os_runtime_args os.runtime_args
 func os_runtime_args() []string { return append([]string{}, argslice...) }
+
+//go:linkname syscall_Exit syscall.Exit
+//go:nosplit
+func syscall_Exit(code int) {
+	exit(int32(code))
+}

src/runtime/syscall_windows.go

@@ -223,9 +223,3 @@ func syscall_Syscall15(fn, nargs, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11,
 	cgocall(asmstdcallAddr, unsafe.Pointer(c))
 	return c.r1, c.r2, c.err
 }
-
-//go:linkname syscall_exit syscall.Exit
-//go:nosplit
-func syscall_exit(code int) {
-	exit(int32(code))
-}

src/syscall/asm_plan9_386.s

@@ -152,12 +152,3 @@ copyresult6:
 	MOVSL
 	MOVSL
 	RET
-
-//func exit(code int)
-// Import runtime·exit for cleanly exiting.
-TEXT ·exit(SB),NOSPLIT,$4-4
-	NO_LOCAL_POINTERS
-	MOVL	code+0(FP), AX
-	MOVL	AX, 0(SP)
-	CALL	runtime·exit(SB)
-	RET

src/syscall/asm_plan9_amd64.s

@@ -150,12 +150,3 @@ copyresult6:
 	MOVSQ
 	MOVSQ
 	RET
-
-//func exit(code int)
-// Import runtime·exit for cleanly exiting.
-TEXT ·exit(SB),NOSPLIT,$8-8
-	NO_LOCAL_POINTERS
-	MOVQ	code+0(FP), AX
-	MOVQ	AX, 0(SP)
-	CALL	runtime·exit(SB)
-	RET

src/syscall/asm_plan9_arm.s

@@ -88,12 +88,3 @@ TEXT ·seek(SB),NOSPLIT,$0-36
 	MOVW	$err+28(FP), R1
 	BL		sysresult<>(SB)
 	RET
-
-//func exit(code int)
-// Import runtime·exit for cleanly exiting.
-TEXT ·exit(SB),NOSPLIT,$4-4
-	NO_LOCAL_POINTERS
-	MOVW	code+0(FP), R0
-	MOVW	R0, e-4(SP)
-	BL		runtime·exit(SB)
-	RET

src/syscall/syscall.go

@@ -96,6 +96,7 @@ func (tv *Timeval) Nano() int64 {
 	return int64(tv.Sec)*1e9 + int64(tv.Usec)*1000
 }
 
-// Getpagesize is provided by the runtime.
+// Getpagesize and Exit are provided by the runtime.
 
 func Getpagesize() int
+func Exit(code int)

src/syscall/syscall_darwin.go

@@ -213,7 +213,6 @@ func Kill(pid int, signum Signal) (err error) { return kill(pid, int(signum), 1)
 //sys	Dup(fd int) (nfd int, err error)
 //sys	Dup2(from int, to int) (err error)
 //sys	Exchangedata(path1 string, path2 string, options int) (err error)
-//sys	Exit(code int)
 //sys	Fchdir(fd int) (err error)
 //sys	Fchflags(fd int, flags int) (err error)
 //sys	Fchmod(fd int, mode uint32) (err error)

src/syscall/syscall_dragonfly.go

@@ -138,7 +138,6 @@ func Getfsstat(buf []Statfs_t, flags int) (n int, err error) {
 //sys	Close(fd int) (err error)
 //sys	Dup(fd int) (nfd int, err error)
 //sys	Dup2(from int, to int) (err error)
-//sys	Exit(code int)
 //sys	Fchdir(fd int) (err error)
 //sys	Fchflags(fd int, flags int) (err error)
 //sys	Fchmod(fd int, mode uint32) (err error)

src/syscall/syscall_freebsd.go

@@ -147,7 +147,6 @@ func Getfsstat(buf []Statfs_t, flags int) (n int, err error) {
 //sys	Close(fd int) (err error)
 //sys	Dup(fd int) (nfd int, err error)
 //sys	Dup2(from int, to int) (err error)
-//sys	Exit(code int)
 //sys	Fchdir(fd int) (err error)
 //sys	Fchflags(fd int, flags int) (err error)
 //sys	Fchmod(fd int, mode uint32) (err error)

src/syscall/syscall_linux.go

@@ -823,7 +823,6 @@ func Mount(source string, target string, fstype string, flags uintptr, data stri
 //sysnb	EpollCreate1(flag int) (fd int, err error)
 //sysnb	EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error)
 //sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
-//sys	Exit(code int) = SYS_EXIT_GROUP
 //sys	Faccessat(dirfd int, path string, mode uint32, flags int) (err error)
 //sys	Fallocate(fd int, mode uint32, off int64, len int64) (err error)
 //sys	Fchdir(fd int) (err error)

src/syscall/syscall_nacl.go

@@ -10,7 +10,6 @@ import (
 )
 
 //sys	naclClose(fd int) (err error) = sys_close
-//sys	Exit(code int) (err error)
 //sys	naclFstat(fd int, stat *Stat_t) (err error) = sys_fstat
 //sys	naclRead(fd int, b []byte) (n int, err error) = sys_read
 //sys	naclSeek(fd int, off *int64, whence int) (err error) = sys_lseek

src/syscall/syscall_netbsd.go

@@ -134,7 +134,6 @@ func sendfile(outfd int, infd int, offset *int64, count int) (written int, err e
 //sys	Close(fd int) (err error)
 //sys	Dup(fd int) (nfd int, err error)
 //sys	Dup2(from int, to int) (err error)
-//sys	Exit(code int)
 //sys	Fchdir(fd int) (err error)
 //sys	Fchflags(fd int, flags int) (err error)
 //sys	Fchmod(fd int, mode uint32) (err error)

src/syscall/syscall_openbsd.go

@@ -112,7 +112,6 @@ func Getfsstat(buf []Statfs_t, flags int) (n int, err error) {
 //sys	Close(fd int) (err error)
 //sys	Dup(fd int) (nfd int, err error)
 //sys	Dup2(from int, to int) (err error)
-//sys	Exit(code int)
 //sys	Fchdir(fd int) (err error)
 //sys	Fchflags(fd int, flags int) (err error)
 //sys	Fchmod(fd int, mode uint32) (err error)

src/syscall/syscall_plan9.go

@@ -85,11 +85,6 @@ func errstr() string {
 	return cstring(buf[:])
 }
 
-// Implemented in assembly to import from runtime.
-func exit(code int)
-
-func Exit(code int) { exit(code) }
-
 func readnum(path string) (uint, error) {
 	var b [12]byte
 

src/syscall/syscall_solaris.go

@@ -436,7 +436,6 @@ func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error)
 //sys	Chroot(path string) (err error)
 //sys	Close(fd int) (err error)
 //sys	Dup(fd int) (nfd int, err error)
-//sys	Exit(code int)
 //sys	Fchdir(fd int) (err error)
 //sys	Fchmod(fd int, mode uint32) (err error)
 //sys	Fchown(fd int, uid int, gid int) (err error)

src/syscall/syscall_windows.go

@@ -236,9 +236,6 @@ func NewCallbackCDecl(fn interface{}) uintptr {
 
 // syscall interface implementation for other packages
 
-// Implemented in ../runtime/syscall_windows.go.
-func Exit(code int)
-
 func makeInheritSa() *SecurityAttributes {
 	var sa SecurityAttributes
 	sa.Length = uint32(unsafe.Sizeof(sa))

src/syscall/zsyscall_darwin_386.go

@@ -444,13 +444,6 @@ func Exchangedata(path1 string, path2 string, options int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Fchdir(fd int) (err error) {
 	_, _, e1 := Syscall(SYS_FCHDIR, uintptr(fd), 0, 0)
 	if e1 != 0 {

src/syscall/zsyscall_darwin_amd64.go

@@ -444,13 +444,6 @@ func Exchangedata(path1 string, path2 string, options int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Fchdir(fd int) (err error) {
 	_, _, e1 := Syscall(SYS_FCHDIR, uintptr(fd), 0, 0)
 	if e1 != 0 {

src/syscall/zsyscall_darwin_arm.go

@@ -444,13 +444,6 @@ func Exchangedata(path1 string, path2 string, options int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Fchdir(fd int) (err error) {
 	_, _, e1 := Syscall(SYS_FCHDIR, uintptr(fd), 0, 0)
 	if e1 != 0 {

src/syscall/zsyscall_darwin_arm64.go

@@ -444,13 +444,6 @@ func Exchangedata(path1 string, path2 string, options int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Fchdir(fd int) (err error) {
 	_, _, e1 := Syscall(SYS_FCHDIR, uintptr(fd), 0, 0)
 	if e1 != 0 {

src/syscall/zsyscall_dragonfly_amd64.go

@@ -438,13 +438,6 @@ func Dup2(from int, to int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Fchdir(fd int) (err error) {
 	_, _, e1 := Syscall(SYS_FCHDIR, uintptr(fd), 0, 0)
 	if e1 != 0 {

src/syscall/zsyscall_freebsd_386.go

@@ -414,13 +414,6 @@ func Dup2(from int, to int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Fchdir(fd int) (err error) {
 	_, _, e1 := Syscall(SYS_FCHDIR, uintptr(fd), 0, 0)
 	if e1 != 0 {

src/syscall/zsyscall_freebsd_amd64.go

@@ -414,13 +414,6 @@ func Dup2(from int, to int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Fchdir(fd int) (err error) {
 	_, _, e1 := Syscall(SYS_FCHDIR, uintptr(fd), 0, 0)
 	if e1 != 0 {

src/syscall/zsyscall_freebsd_arm.go

@@ -414,13 +414,6 @@ func Dup2(from int, to int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Fchdir(fd int) (err error) {
 	_, _, e1 := Syscall(SYS_FCHDIR, uintptr(fd), 0, 0)
 	if e1 != 0 {

src/syscall/zsyscall_linux_386.go

@@ -356,13 +356,6 @@ func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT_GROUP, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)

src/syscall/zsyscall_linux_amd64.go

@@ -356,13 +356,6 @@ func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT_GROUP, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)

src/syscall/zsyscall_linux_arm.go

@@ -356,13 +356,6 @@ func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT_GROUP, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)

src/syscall/zsyscall_linux_arm64.go

@@ -356,13 +356,6 @@ func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT_GROUP, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)

src/syscall/zsyscall_linux_mips.go

@@ -356,13 +356,6 @@ func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT_GROUP, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)

src/syscall/zsyscall_linux_mips64.go

@@ -356,13 +356,6 @@ func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT_GROUP, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)

src/syscall/zsyscall_linux_mips64le.go

@@ -356,13 +356,6 @@ func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT_GROUP, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)

src/syscall/zsyscall_linux_mipsle.go

@@ -356,13 +356,6 @@ func EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
-func Exit(code int) {
-	Syscall(SYS_EXIT_GROUP, uintptr(code), 0, 0)
-	return
-}
-
-// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
-
 func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)