all: remove support for windows/arm

Also CL 690655 for golang.org/x/sys.

For #71671

Change-Id: Iceb369dec5affb944a39d07cdabfd7add6f1f319
Reviewed-on: https://go-review.googlesource.com/c/go/+/648795
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Quim Muntal <quimmuntal@gmail.com>
Reviewed-by: Mark Freeman <markfreeman@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

doc/next/7-ports.md

@@ -1,2 +1,6 @@
 ## Ports {#ports}
 
+### Windows
+
+<!-- go.dev/issue/71671 -->
+As [announced](/doc/go1.25#windows) in the Go 1.25 release notes, the [broken](/doc/go1.24#windows) 32-bit windows/arm port (`GOOS=windows` `GOARCH=arm`) is removed.

src/cmd/dist/build.go

@@ -1819,7 +1819,6 @@ var cgoEnabled = map[string]bool{
 	"solaris/amd64":   true,
 	"windows/386":     true,
 	"windows/amd64":   true,
-	"windows/arm":     false,
 	"windows/arm64":   true,
 }
 
@@ -1831,7 +1830,6 @@ var broken = map[string]bool{
 	"freebsd/riscv64": true, // Broken: go.dev/issue/73568.
 	"linux/sparc64":   true, // An incomplete port. See CL 132155.
 	"openbsd/mips64":  true, // Broken: go.dev/issue/58110.
-	"windows/arm":     true, // Broken: go.dev/issue/68552.
 }
 
 // List of platforms which are first class ports. See go.dev/issue/38874.

src/cmd/dist/sys_windows.go

@@ -33,7 +33,6 @@ type systeminfo struct {
 const (
 	PROCESSOR_ARCHITECTURE_AMD64 = 9
 	PROCESSOR_ARCHITECTURE_INTEL = 0
-	PROCESSOR_ARCHITECTURE_ARM   = 5
 	PROCESSOR_ARCHITECTURE_ARM64 = 12
 	PROCESSOR_ARCHITECTURE_IA64  = 6
 )
@@ -47,8 +46,6 @@ func sysinit() {
 		gohostarch = "amd64"
 	case PROCESSOR_ARCHITECTURE_INTEL:
 		gohostarch = "386"
-	case PROCESSOR_ARCHITECTURE_ARM:
-		gohostarch = "arm"
 	case PROCESSOR_ARCHITECTURE_ARM64:
 		gohostarch = "arm64"
 	default:

src/cmd/internal/objfile/pe.go

@@ -174,8 +174,6 @@ func (f *peFile) goarch() string {
 		return "386"
 	case pe.IMAGE_FILE_MACHINE_AMD64:
 		return "amd64"
-	case pe.IMAGE_FILE_MACHINE_ARMNT:
-		return "arm"
 	case pe.IMAGE_FILE_MACHINE_ARM64:
 		return "arm64"
 	default:

src/cmd/link/internal/arm/obj.go

@@ -105,9 +105,5 @@ func archinit(ctxt *ld.Link) {
 		if *ld.FlagTextAddr == -1 {
 			*ld.FlagTextAddr = ld.Rnd(0x10000, *ld.FlagRound) + int64(ld.HEADR)
 		}
-
-	case objabi.Hwindows: /* PE executable */
-		// ld.HEADR, ld.FlagTextAddr, ld.FlagRound are set in ld.Peinit
-		return
 	}
 }

src/cmd/link/internal/ld/config.go

@@ -34,7 +34,7 @@ func (mode *BuildMode) Set(s string) error {
 		return fmt.Errorf("invalid buildmode: %q", s)
 	case "exe":
 		switch buildcfg.GOOS + "/" + buildcfg.GOARCH {
-		case "darwin/arm64", "windows/arm", "windows/arm64": // On these platforms, everything is PIE
+		case "darwin/arm64", "windows/arm64": // On these platforms, everything is PIE
 			*mode = BuildModePIE
 		default:
 			*mode = BuildModeExe

src/cmd/link/internal/ld/pe.go

@@ -913,8 +913,6 @@ func (f *peFile) writeFileHeader(ctxt *Link) {
 		fh.Machine = pe.IMAGE_FILE_MACHINE_AMD64
 	case sys.I386:
 		fh.Machine = pe.IMAGE_FILE_MACHINE_I386
-	case sys.ARM:
-		fh.Machine = pe.IMAGE_FILE_MACHINE_ARMNT
 	case sys.ARM64:
 		fh.Machine = pe.IMAGE_FILE_MACHINE_ARM64
 	}

src/internal/platform/supported.go

@@ -194,7 +194,7 @@ func BuildModeSupported(compiler, buildmode, goos, goarch string) bool {
 			"ios/amd64", "ios/arm64",
 			"aix/ppc64",
 			"openbsd/arm64",
-			"windows/386", "windows/amd64", "windows/arm", "windows/arm64":
+			"windows/386", "windows/amd64", "windows/arm64":
 			return true
 		}
 		return false
@@ -226,7 +226,7 @@ func InternalLinkPIESupported(goos, goarch string) bool {
 	case "android/arm64",
 		"darwin/amd64", "darwin/arm64",
 		"linux/amd64", "linux/arm64", "linux/loong64", "linux/ppc64le",
-		"windows/386", "windows/amd64", "windows/arm", "windows/arm64":
+		"windows/386", "windows/amd64", "windows/arm64":
 		return true
 	}
 	return false

src/internal/platform/zosarch.go

@@ -57,7 +57,6 @@ var List = []OSArch{
 	{"wasip1", "wasm"},
 	{"windows", "386"},
 	{"windows", "amd64"},
-	{"windows", "arm"},
 	{"windows", "arm64"},
 }
 
@@ -111,6 +110,5 @@ var distInfo = map[OSArch]osArchInfo{
 	{"wasip1", "wasm"}:     {},
 	{"windows", "386"}:     {CgoSupported: true, FirstClass: true},
 	{"windows", "amd64"}:   {CgoSupported: true, FirstClass: true},
-	{"windows", "arm"}:     {Broken: true},
 	{"windows", "arm64"}:   {CgoSupported: true},
 }

src/runtime/asm_arm.s

@@ -794,9 +794,6 @@ TEXT setg<>(SB),NOSPLIT|NOFRAME,$0-0
 	MOVW	R0, g
 
 	// Save g to thread-local storage.
-#ifdef GOOS_windows
-	B	runtime·save_g(SB)
-#else
 #ifdef GOOS_openbsd
 	B	runtime·save_g(SB)
 #else
@@ -808,7 +805,6 @@ TEXT setg<>(SB),NOSPLIT|NOFRAME,$0-0
 	MOVW	g, R0
 	RET
 #endif
-#endif
 
 TEXT runtime·emptyfunc(SB),0,$0-0
 	RET

src/runtime/pprof/pprof_test.go

@@ -635,10 +635,6 @@ func TestCPUProfileWithFork(t *testing.T) {
 		// Use smaller size for Android to avoid crash.
 		heap = 100 << 20
 	}
-	if runtime.GOOS == "windows" && runtime.GOARCH == "arm" {
-		// Use smaller heap for Windows/ARM to avoid crash.
-		heap = 100 << 20
-	}
 	if testing.Short() {
 		heap = 100 << 20
 	}

src/runtime/rt0_windows_arm.s

@@ -1,12 +0,0 @@
-// Copyright 2018 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.
-
-#include "go_asm.h"
-#include "go_tls.h"
-#include "textflag.h"
-
-// This is the entry point for the program from the
-// kernel for an ordinary -buildmode=exe program.
-TEXT _rt0_arm_windows(SB),NOSPLIT|NOFRAME,$0
-	B	·rt0_go(SB)

src/runtime/signal_windows.go

@@ -39,7 +39,7 @@ func enableWER() {
 	}
 }
 
-// in sys_windows_386.s, sys_windows_amd64.s, sys_windows_arm.s, and sys_windows_arm64.s
+// in sys_windows_386.s, sys_windows_amd64.s, and sys_windows_arm64.s
 func exceptiontramp()
 func firstcontinuetramp()
 func lastcontinuetramp()
@@ -64,10 +64,9 @@ func initExceptionHandler() {
 //go:nosplit
 func isAbort(r *context) bool {
 	pc := r.ip()
-	if GOARCH == "386" || GOARCH == "amd64" || GOARCH == "arm" {
+	if GOARCH == "386" || GOARCH == "amd64" {
 		// In the case of an abort, the exception IP is one byte after
-		// the INT3 (this differs from UNIX OSes). Note that on ARM,
+		// the INT3 (this differs from UNIX OSes).
-		// this means that the exception IP is no longer aligned.
 		pc--
 	}
 	return isAbortPC(pc)

src/runtime/syscall_windows.go

@@ -236,7 +236,7 @@ func callbackasm()
 // and we want callback to arrive at
 // correspondent call instruction instead of start of
 // runtime.callbackasm.
-// On ARM, runtime.callbackasm is a series of mov and branch instructions.
+// On ARM64, runtime.callbackasm is a series of mov and branch instructions.
 // R12 is loaded with the callback index. Each entry is two instructions,
 // hence 8 bytes.
 func callbackasmAddr(i int) uintptr {
@@ -246,8 +246,8 @@ func callbackasmAddr(i int) uintptr {
 		panic("unsupported architecture")
 	case "386", "amd64":
 		entrySize = 5
-	case "arm", "arm64":
+	case "arm64":
-		// On ARM and ARM64, each entry is a MOV instruction
+		// On ARM64, each entry is a MOV instruction
 		// followed by a branch instruction
 		entrySize = 8
 	}

src/runtime/time_windows_arm.s

@@ -1,84 +0,0 @@
-// Copyright 2018 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 !faketime
-
-#include "go_asm.h"
-#include "textflag.h"
-#include "time_windows.h"
-
-TEXT time·now(SB),NOSPLIT,$0-20
-	MOVW	$_INTERRUPT_TIME, R3
-loop:
-	MOVW	time_hi1(R3), R1
-	DMB	MB_ISH
-	MOVW	time_lo(R3), R0
-	DMB	MB_ISH
-	MOVW	time_hi2(R3), R2
-	CMP	R1, R2
-	BNE	loop
-
-	// wintime = R1:R0, multiply by 100
-	MOVW	$100, R2
-	MULLU	R0, R2, (R4, R3)    // R4:R3 = R1:R0 * R2
-	MULA	R1, R2, R4, R4
-
-	// wintime*100 = R4:R3
-	MOVW	R3, mono+12(FP)
-	MOVW	R4, mono+16(FP)
-
-	MOVW	$_SYSTEM_TIME, R3
-wall:
-	MOVW	time_hi1(R3), R1
-	DMB	MB_ISH
-	MOVW	time_lo(R3), R0
-	DMB	MB_ISH
-	MOVW	time_hi2(R3), R2
-	CMP	R1, R2
-	BNE	wall
-
-	// w = R1:R0 in 100ns untis
-	// convert to Unix epoch (but still 100ns units)
-	#define delta 116444736000000000
-	SUB.S   $(delta & 0xFFFFFFFF), R0
-	SBC     $(delta >> 32), R1
-
-	// Convert to nSec
-	MOVW    $100, R2
-	MULLU   R0, R2, (R4, R3)    // R4:R3 = R1:R0 * R2
-	MULA    R1, R2, R4, R4
-	// w = R2:R1 in nSec
-	MOVW    R3, R1	      // R4:R3 -> R2:R1
-	MOVW    R4, R2
-
-	// multiply nanoseconds by reciprocal of 10**9 (scaled by 2**61)
-	// to get seconds (96 bit scaled result)
-	MOVW	$0x89705f41, R3		// 2**61 * 10**-9
-	MULLU	R1,R3,(R6,R5)		// R7:R6:R5 = R2:R1 * R3
-	MOVW	$0,R7
-	MULALU	R2,R3,(R7,R6)
-
-	// unscale by discarding low 32 bits, shifting the rest by 29
-	MOVW	R6>>29,R6		// R7:R6 = (R7:R6:R5 >> 61)
-	ORR	R7<<3,R6
-	MOVW	R7>>29,R7
-
-	// subtract (10**9 * sec) from nsec to get nanosecond remainder
-	MOVW	$1000000000, R5	// 10**9
-	MULLU	R6,R5,(R9,R8)   // R9:R8 = R7:R6 * R5
-	MULA	R7,R5,R9,R9
-	SUB.S	R8,R1		// R2:R1 -= R9:R8
-	SBC	R9,R2
-
-	// because reciprocal was a truncated repeating fraction, quotient
-	// may be slightly too small -- adjust to make remainder < 10**9
-	CMP	R5,R1	// if remainder > 10**9
-	SUB.HS	R5,R1   //    remainder -= 10**9
-	ADD.HS	$1,R6	//    sec += 1
-
-	MOVW	R6,sec_lo+0(FP)
-	MOVW	R7,sec_hi+4(FP)
-	MOVW	R1,nsec+8(FP)
-	RET
-

src/runtime/wincallback.go

@@ -47,34 +47,6 @@ TEXT runtime·callbackasm(SB),NOSPLIT|NOFRAME,$0
 	}
 }
 
-func genasmArm() {
-	var buf bytes.Buffer
-
-	buf.WriteString(`// Code generated by wincallback.go using 'go generate'. DO NOT EDIT.
-
-// External code calls into callbackasm at an offset corresponding
-// to the callback index. Callbackasm is a table of MOV and B instructions.
-// The MOV instruction loads R12 with the callback index, and the
-// B instruction branches to callbackasm1.
-// callbackasm1 takes the callback index from R12 and
-// indexes into an array that stores information about each callback.
-// It then calls the Go implementation for that callback.
-#include "textflag.h"
-
-TEXT runtime·callbackasm(SB),NOSPLIT|NOFRAME,$0
-`)
-	for i := 0; i < maxCallback; i++ {
-		fmt.Fprintf(&buf, "\tMOVW\t$%d, R12\n", i)
-		buf.WriteString("\tB\truntime·callbackasm1(SB)\n")
-	}
-
-	err := os.WriteFile("zcallback_windows_arm.s", buf.Bytes(), 0666)
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "wincallback: %s\n", err)
-		os.Exit(2)
-	}
-}
-
 func genasmArm64() {
 	var buf bytes.Buffer
 
@@ -121,7 +93,6 @@ const cb_max = %d // maximum number of windows callbacks allowed
 
 func main() {
 	genasm386Amd64()
-	genasmArm()
 	genasmArm64()
 	gengo()
 }

src/syscall/syscall_windows.go

@@ -14,7 +14,6 @@ import (
 	"internal/msan"
 	"internal/oserror"
 	"internal/race"
-	"runtime"
 	"sync"
 	"unsafe"
 )
@@ -525,18 +524,8 @@ func setFilePointerEx(handle Handle, distToMove int64, newFilePointer *int64, wh
 	if unsafe.Sizeof(uintptr(0)) == 8 {
 		_, _, e1 = Syscall6(procSetFilePointerEx.Addr(), 4, uintptr(handle), uintptr(distToMove), uintptr(unsafe.Pointer(newFilePointer)), uintptr(whence), 0, 0)
 	} else {
-		// Different 32-bit systems disgaree about whether distToMove starts 8-byte aligned.
-		switch runtime.GOARCH {
-		default:
-			panic("unsupported 32-bit architecture")
-		case "386":
 		// distToMove is a LARGE_INTEGER, which is 64 bits.
 		_, _, e1 = Syscall6(procSetFilePointerEx.Addr(), 5, uintptr(handle), uintptr(distToMove), uintptr(distToMove>>32), uintptr(unsafe.Pointer(newFilePointer)), uintptr(whence), 0)
-		case "arm":
-			// distToMove must be 8-byte aligned per ARM calling convention
-			// https://docs.microsoft.com/en-us/cpp/build/overview-of-arm-abi-conventions#stage-c-assignment-of-arguments-to-registers-and-stack
-			_, _, e1 = Syscall6(procSetFilePointerEx.Addr(), 6, uintptr(handle), 0, uintptr(distToMove), uintptr(distToMove>>32), uintptr(unsafe.Pointer(newFilePointer)), uintptr(whence))
-		}
 	}
 	if e1 != 0 {
 		return errnoErr(e1)

src/syscall/types_windows_arm.go

@@ -1,22 +0,0 @@
-// Copyright 2018 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.
-
-package syscall
-
-type WSAData struct {
-	Version      uint16
-	HighVersion  uint16
-	Description  [WSADESCRIPTION_LEN + 1]byte
-	SystemStatus [WSASYS_STATUS_LEN + 1]byte
-	MaxSockets   uint16
-	MaxUdpDg     uint16
-	VendorInfo   *byte
-}
-
-type Servent struct {
-	Name    *byte
-	Aliases **byte
-	Port    uint16
-	Proto   *byte
-}