unix: generate linux/sparc64 go files using Docker

With cgo supporting sparc64 as of CL 102555 and CL 132155, the Docker
based build system can be used to generate file for linux/sparc64 as
well.

Updates golang/go#15282

Change-Id: I109e55f39d3229b24b0029c42074e439c6c54dc8
Reviewed-on: https://go-review.googlesource.com/c/102655
Run-TryBot: Tobias Klauser <[email protected]>
TryBot-Result: Gobot Gobot <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>

Author: tklauser

unix/README.md

@@ -14,7 +14,7 @@ migrating the build system to use containers so the builds are reproducible.
 This is being done on an OS-by-OS basis. Please update this documentation as
 components of the build system change.
 
-### Old Build System (currently for `GOOS != "Linux" || GOARCH == "sparc64"`)
+### Old Build System (currently for `GOOS != "linux"`)
 
 The old build system generates the Go files based on the C header files
 present on your system. This means that files
@@ -34,7 +34,7 @@ your specific system. Running `mkall.sh -n` shows the commands that will be run.
 
 Requirements: bash, perl, go
 
-### New Build System (currently for `GOOS == "Linux" && GOARCH != "sparc64"`)
+### New Build System (currently for `GOOS == "linux"`)
 
 The new build system uses a Docker container to generate the go files directly
 from source checkouts of the kernel and various system libraries. This means

unix/linux/mkall.go

@@ -52,8 +52,9 @@ type target struct {
 	Bits       int
 }
 
-// List of all Linux targets supported by the go compiler. sparc64 is not
-// currently supported, though a port is in progress.
+// List of all Linux targets supported by the go compiler. Currently, riscv64
+// and sparc64 are not fully supported, but there is enough support already to
+// generate Go type and error definitions.
 var targets = []target{
 	{
 		GoArch:    "386",
@@ -133,13 +134,13 @@ var targets = []target{
 		SignedChar: true,
 		Bits:       64,
 	},
-	// {
-	// 	GoArch:    "sparc64",
-	// 	LinuxArch: "sparc",
-	// 	GNUArch:   "sparc64-linux-gnu",
-	// 	BigEndian: true,
-	// 	Bits:      64,
-	// },
+	{
+		GoArch:    "sparc64",
+		LinuxArch: "sparc",
+		GNUArch:   "sparc64-linux-gnu",
+		BigEndian: true,
+		Bits:      64,
+	},
 }
 
 // ptracePairs is a list of pairs of targets that can, in some cases,
@@ -532,7 +533,7 @@ func (t *target) mksyscallFlags() (flags []string) {
 		}
 	}
 
-	// This flag menas a 64-bit value should use (even, odd)-pair.
+	// This flag means a 64-bit value should use (even, odd)-pair.
 	if t.GoArch == "arm" || (t.LinuxArch == "mips" && t.Bits == 32) {
 		flags = append(flags, "-arm")
 	}

unix/linux/types.go

@@ -57,7 +57,28 @@ package unix
 #include <linux/perf_event.h>
 #include <linux/rtnetlink.h>
 #include <linux/stat.h>
+#if defined(__sparc__)
+// On sparc{,64}, the kernel defines struct termios2 itself which clashes with the
+// definition in glibc. Duplicate the kernel version here.
+#if defined(__arch64__)
+typedef unsigned int tcflag_t;
+#else
+typedef unsigned long tcflag_t;
+#endif
+
+struct termios2 {
+	tcflag_t c_iflag;
+	tcflag_t c_oflag;
+	tcflag_t c_cflag;
+	tcflag_t c_lflag;
+	unsigned char c_line;
+	unsigned char c_cc[19];
+	unsigned int c_ispeed;
+	unsigned int c_ospeed;
+};
+#else
 #include <asm/termbits.h>
+#endif
 #include <asm/ptrace.h>
 #include <time.h>
 #include <unistd.h>

unix/mkall.sh

@@ -46,8 +46,8 @@ case "$#" in
 	exit 2
 esac
 
-if [[ "$GOOS" = "linux" ]] && [[ "$GOARCH" != "sparc64" ]]; then
-	# Use then new build system
+if [[ "$GOOS" = "linux" ]]; then
+	# Use the Docker-based build system
 	# Files generated through docker (use $cmd so you can Ctl-C the build or run)
 	$cmd docker build --tag generate:$GOOS $GOOS
 	$cmd docker run --interactive --tty --volume $(dirname "$(readlink -f "$0")"):/build generate:$GOOS
@@ -121,13 +121,6 @@ freebsd_arm)
 	# API consistent across platforms.
 	mktypes="GOARCH=$GOARCH go tool cgo -godefs -- -fsigned-char"
 	;;
-linux_sparc64)
-	GOOSARCH_in=syscall_linux_sparc64.go
-	unistd_h=/usr/include/sparc64-linux-gnu/asm/unistd.h
-	mkerrors="$mkerrors -m64"
-	mksysnum="./mksysnum_linux.pl $unistd_h"
-	mktypes="GOARCH=$GOARCH go tool cgo -godefs"
-	;;
 netbsd_386)
 	mkerrors="$mkerrors -m32"
 	mksyscall="go run mksyscall.go -l32 -netbsd"

unix/mkerrors.sh

@@ -17,12 +17,10 @@ if test -z "$GOARCH" -o -z "$GOOS"; then
 fi
 
 # Check that we are using the new build system if we should
-if [[ "$GOOS" = "linux" ]] && [[ "$GOARCH" != "sparc64" ]]; then
-	if [[ "$GOLANG_SYS_BUILD" != "docker" ]]; then
-		echo 1>&2 "In the new build system, mkerrors should not be called directly."
-		echo 1>&2 "See README.md"
-		exit 1
-	fi
+if [[ "$GOOS" = "linux" ]] && [[ "$GOLANG_SYS_BUILD" != "docker" ]]; then
+	echo 1>&2 "In the Docker based build system, mkerrors should not be called directly."
+	echo 1>&2 "See README.md"
+	exit 1
 fi
 
 if [[ "$GOOS" = "aix" ]]; then
@@ -223,7 +221,15 @@ struct ltchars {
 #include <linux/if_xdp.h>
 #include <mtd/ubi-user.h>
 #include <net/route.h>
+
+#if defined(__sparc__)
+// On sparc{,64}, the kernel defines struct termios2 itself which clashes with the
+// definition in glibc. As only the error constants are needed here, include the
+// generic termibits.h (which is included by termbits.h on sparc).
+#include <asm-generic/termbits.h>
+#else
 #include <asm/termbits.h>
+#endif
 
 #ifndef MSG_FASTOPEN
 #define MSG_FASTOPEN    0x20000000

unix/mkpost.go

@@ -28,10 +28,10 @@ func main() {
 	if goarch == "" {
 		goarch = os.Getenv("GOARCH")
 	}
-	// Check that we are using the new build system if we should be.
-	if goos == "linux" && goarch != "sparc64" {
+	// Check that we are using the Docker-based build system if we should be.
+	if goos == "linux" {
 		if os.Getenv("GOLANG_SYS_BUILD") != "docker" {
-			os.Stderr.WriteString("In the new build system, mkpost should not be called directly.\n")
+			os.Stderr.WriteString("In the Docker-based build system, mkpost should not be called directly.\n")
 			os.Stderr.WriteString("See README.md\n")
 			os.Exit(1)
 		}

unix/mksyscall.go

@@ -93,10 +93,10 @@ func main() {
 		goarch = os.Getenv("GOARCH")
 	}
 
-	// Check that we are using the new build system if we should
-	if goos == "linux" && goarch != "sparc64" {
+	// Check that we are using the Docker-based build system if we should
+	if goos == "linux" {
 		if os.Getenv("GOLANG_SYS_BUILD") != "docker" {
-			fmt.Fprintf(os.Stderr, "In the new build system, mksyscall should not be called directly.\n")
+			fmt.Fprintf(os.Stderr, "In the Docker-based build system, mksyscall should not be called directly.\n")
 			fmt.Fprintf(os.Stderr, "See README.md\n")
 			os.Exit(1)
 		}