cmd/link/internal/ld,syscall: drop $INODE64 suffixes on simulators

Some libc functions are suffixed with "$INODE64" on macOS.
Unfortunately, the iOS simulator doesn't have the suffixes, so we can't
use GOARCH to distinguish the two platform.

Add linker support for adding the suffix, using the macho platform
to determine whether it is needed.

While here, add the correct suffix for fdopendir on 386. It's
"$INODE64$UNIX2003", believe it or not. Without the suffix,

GOARCH=386 go test -short syscall

crashes on my Mojave machine.

Fixes #31447

Change-Id: I9bd3de40ece7df62f744bc24cd00909e56b00b78
Reviewed-on: https://go-review.googlesource.com/c/go/+/174199
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

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

@@ -786,6 +786,27 @@ func (x machoscmp) Less(i, j int) bool {
 func machogenasmsym(ctxt *Link) {
 	genasmsym(ctxt, addsym)
 	for _, s := range ctxt.Syms.Allsym {
+		// Some 64-bit functions have a "$INODE64" or "$INODE64$UNIX2003" suffix.
+		if s.Type == sym.SDYNIMPORT && s.Dynimplib() == "/usr/lib/libSystem.B.dylib" {
+			// But only on macOS.
+			if machoPlatform == PLATFORM_MACOS {
+				switch n := s.Extname(); n {
+				case "fdopendir":
+					switch objabi.GOARCH {
+					case "amd64":
+						s.SetExtname(n + "$INODE64")
+					case "386":
+						s.SetExtname(n + "$INODE64$UNIX2003")
+					}
+				case "readdir_r":
+					switch objabi.GOARCH {
+					case "amd64", "386":
+						s.SetExtname(n + "$INODE64")
+					}
+				}
+			}
+		}
+
 		if s.Type == sym.SDYNIMPORT || s.Type == sym.SHOSTOBJ {
 			if s.Attr.Reachable() {
 				addsym(ctxt, s, "", DataSym, 0, nil)

src/syscall/mksyscall.pl

@@ -350,10 +350,6 @@ while(<>) {
 			$text .= "//go:linkname $funcname $funcname\n";
 			# Tell the linker that funcname can be found in libSystem using varname without the libc_ prefix.
 			my $basename = substr $funcname, 5;
-			if($basename eq "readdir_r" && ($ENV{'GOARCH'} eq "386" || $ENV{'GOARCH'} eq "amd64")) {
-			    # Hack to make sure we get the 64-bit inode version on darwin/macOS.
-			    $basename .= "\$INODE64"
-			}
 			$text .= "//go:cgo_import_dynamic $funcname $basename \"/usr/lib/libSystem.B.dylib\"\n\n";
 		}
 	}

src/syscall/syscall_darwin.go

@@ -347,6 +347,20 @@ func init() {
 	execveDarwin = execve
 }
 
+func fdopendir(fd int) (dir uintptr, err error) {
+	r0, _, e1 := syscallPtr(funcPC(libc_fdopendir_trampoline), uintptr(fd), 0, 0)
+	dir = uintptr(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+func libc_fdopendir_trampoline()
+
+//go:linkname libc_fdopendir libc_fdopendir
+//go:cgo_import_dynamic libc_fdopendir fdopendir "/usr/lib/libSystem.B.dylib"
+
 func readlen(fd int, buf *byte, nbuf int) (n int, err error) {
 	r0, _, e1 := syscall(funcPC(libc_read_trampoline), uintptr(fd), uintptr(unsafe.Pointer(buf)), uintptr(nbuf))
 	n = int(r0)

src/syscall/syscall_darwin_386.go

@@ -58,20 +58,6 @@ func libc_sendfile_trampoline()
 //go:linkname libc_sendfile libc_sendfile
 //go:cgo_import_dynamic libc_sendfile sendfile "/usr/lib/libSystem.B.dylib"
 
-func fdopendir(fd int) (dir uintptr, err error) {
-	r0, _, e1 := syscallPtr(funcPC(libc_fdopendir_trampoline), uintptr(fd), 0, 0)
-	dir = uintptr(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fdopendir_trampoline()
-
-//go:linkname libc_fdopendir libc_fdopendir
-//go:cgo_import_dynamic libc_fdopendir fdopendir "/usr/lib/libSystem.B.dylib"
-
 // Implemented in the runtime package (runtime/sys_darwin_32.go)
 func syscall9(fn, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr, err Errno)
 

src/syscall/syscall_darwin_amd64.go

@@ -58,20 +58,6 @@ func libc_sendfile_trampoline()
 //go:linkname libc_sendfile libc_sendfile
 //go:cgo_import_dynamic libc_sendfile sendfile "/usr/lib/libSystem.B.dylib"
 
-func fdopendir(fd int) (dir uintptr, err error) {
-	r0, _, e1 := syscallPtr(funcPC(libc_fdopendir_trampoline), uintptr(fd), 0, 0)
-	dir = uintptr(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fdopendir_trampoline()
-
-//go:linkname libc_fdopendir libc_fdopendir
-//go:cgo_import_dynamic libc_fdopendir fdopendir$INODE64 "/usr/lib/libSystem.B.dylib"
-
 // Implemented in the runtime package (runtime/sys_darwin_64.go)
 func syscallX(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
 

src/syscall/syscall_darwin_arm.go

@@ -58,20 +58,6 @@ func libc_sendfile_trampoline()
 //go:linkname libc_sendfile libc_sendfile
 //go:cgo_import_dynamic libc_sendfile sendfile "/usr/lib/libSystem.B.dylib"
 
-func fdopendir(fd int) (dir uintptr, err error) {
-	r0, _, e1 := syscallPtr(funcPC(libc_fdopendir_trampoline), uintptr(fd), 0, 0)
-	dir = uintptr(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fdopendir_trampoline()
-
-//go:linkname libc_fdopendir libc_fdopendir
-//go:cgo_import_dynamic libc_fdopendir fdopendir "/usr/lib/libSystem.B.dylib"
-
 // Implemented in the runtime package (runtime/sys_darwin_32.go)
 func syscall9(fn, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2 uintptr, err Errno)
 

src/syscall/syscall_darwin_arm64.go

@@ -58,20 +58,6 @@ func libc_sendfile_trampoline()
 //go:linkname libc_sendfile libc_sendfile
 //go:cgo_import_dynamic libc_sendfile sendfile "/usr/lib/libSystem.B.dylib"
 
-func fdopendir(fd int) (dir uintptr, err error) {
-	r0, _, e1 := syscallPtr(funcPC(libc_fdopendir_trampoline), uintptr(fd), 0, 0)
-	dir = uintptr(r0)
-	if e1 != 0 {
-		err = errnoErr(e1)
-	}
-	return
-}
-
-func libc_fdopendir_trampoline()
-
-//go:linkname libc_fdopendir libc_fdopendir
-//go:cgo_import_dynamic libc_fdopendir fdopendir "/usr/lib/libSystem.B.dylib"
-
 // Implemented in the runtime package (runtime/sys_darwin_64.go)
 func syscallX(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
 

src/syscall/zsyscall_darwin_386.go

@@ -1278,7 +1278,7 @@ func readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno) {
 func libc_readdir_r_trampoline()
 
 //go:linkname libc_readdir_r libc_readdir_r
-//go:cgo_import_dynamic libc_readdir_r readdir_r$INODE64 "/usr/lib/libSystem.B.dylib"
+//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
 

src/syscall/zsyscall_darwin_amd64.go

@@ -1278,7 +1278,7 @@ func readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno) {
 func libc_readdir_r_trampoline()
 
 //go:linkname libc_readdir_r libc_readdir_r
-//go:cgo_import_dynamic libc_readdir_r readdir_r$INODE64 "/usr/lib/libSystem.B.dylib"
+//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
 

src/syscall/zsyscall_darwin_arm.s

@@ -7,10 +7,10 @@ TEXT ·libc_getfsstat64_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_getfsstat64(SB)
 TEXT ·libc_setattrlist_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_setattrlist(SB)
-TEXT ·libc_sendfile_trampoline(SB),NOSPLIT,$0-0
-	JMP	libc_sendfile(SB)
 TEXT ·libc_fdopendir_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_fdopendir(SB)
+TEXT ·libc_sendfile_trampoline(SB),NOSPLIT,$0-0
+	JMP	libc_sendfile(SB)
 TEXT ·libc_getgroups_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_getgroups(SB)
 TEXT ·libc_setgroups_trampoline(SB),NOSPLIT,$0-0
@@ -75,6 +75,8 @@ TEXT ·libc_chroot_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_chroot(SB)
 TEXT ·libc_close_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_close(SB)
+TEXT ·libc_closedir_trampoline(SB),NOSPLIT,$0-0
+	JMP	libc_closedir(SB)
 TEXT ·libc_dup_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_dup(SB)
 TEXT ·libc_dup2_trampoline(SB),NOSPLIT,$0-0
@@ -159,6 +161,8 @@ TEXT ·libc_pwrite_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_pwrite(SB)
 TEXT ·libc_read_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_read(SB)
+TEXT ·libc_readdir_r_trampoline(SB),NOSPLIT,$0-0
+	JMP	libc_readdir_r(SB)
 TEXT ·libc_readlink_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_readlink(SB)
 TEXT ·libc_rename_trampoline(SB),NOSPLIT,$0-0
@@ -233,8 +237,6 @@ TEXT ·libc_unlinkat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_unlinkat(SB)
 TEXT ·libc_openat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_openat(SB)
-TEXT ·libc_closedir_trampoline(SB),NOSPLIT,$0-0
-	JMP	libc_closedir(SB)
 TEXT ·libc_fstat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_fstat(SB)
 TEXT ·libc_fstatfs_trampoline(SB),NOSPLIT,$0-0
@@ -243,8 +245,6 @@ TEXT ·libc_gettimeofday_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_gettimeofday(SB)
 TEXT ·libc_lstat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_lstat(SB)
-TEXT ·libc_readdir_r_trampoline(SB),NOSPLIT,$0-0
-	JMP	libc_readdir_r(SB)
 TEXT ·libc_stat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_stat(SB)
 TEXT ·libc_statfs_trampoline(SB),NOSPLIT,$0-0

src/syscall/zsyscall_darwin_arm64.s

@@ -7,10 +7,10 @@ TEXT ·libc_getfsstat64_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_getfsstat64(SB)
 TEXT ·libc_setattrlist_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_setattrlist(SB)
-TEXT ·libc_sendfile_trampoline(SB),NOSPLIT,$0-0
-	JMP	libc_sendfile(SB)
 TEXT ·libc_fdopendir_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_fdopendir(SB)
+TEXT ·libc_sendfile_trampoline(SB),NOSPLIT,$0-0
+	JMP	libc_sendfile(SB)
 TEXT ·libc_getgroups_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_getgroups(SB)
 TEXT ·libc_setgroups_trampoline(SB),NOSPLIT,$0-0
@@ -75,6 +75,8 @@ TEXT ·libc_chroot_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_chroot(SB)
 TEXT ·libc_close_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_close(SB)
+TEXT ·libc_closedir_trampoline(SB),NOSPLIT,$0-0
+	JMP	libc_closedir(SB)
 TEXT ·libc_dup_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_dup(SB)
 TEXT ·libc_dup2_trampoline(SB),NOSPLIT,$0-0
@@ -159,6 +161,8 @@ TEXT ·libc_pwrite_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_pwrite(SB)
 TEXT ·libc_read_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_read(SB)
+TEXT ·libc_readdir_r_trampoline(SB),NOSPLIT,$0-0
+	JMP	libc_readdir_r(SB)
 TEXT ·libc_readlink_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_readlink(SB)
 TEXT ·libc_rename_trampoline(SB),NOSPLIT,$0-0
@@ -233,8 +237,6 @@ TEXT ·libc_unlinkat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_unlinkat(SB)
 TEXT ·libc_openat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_openat(SB)
-TEXT ·libc_closedir_trampoline(SB),NOSPLIT,$0-0
-	JMP	libc_closedir(SB)
 TEXT ·libc_fstat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_fstat(SB)
 TEXT ·libc_fstatfs_trampoline(SB),NOSPLIT,$0-0
@@ -243,8 +245,6 @@ TEXT ·libc_gettimeofday_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_gettimeofday(SB)
 TEXT ·libc_lstat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_lstat(SB)
-TEXT ·libc_readdir_r_trampoline(SB),NOSPLIT,$0-0
-	JMP	libc_readdir_r(SB)
 TEXT ·libc_stat_trampoline(SB),NOSPLIT,$0-0
 	JMP	libc_stat(SB)
 TEXT ·libc_statfs_trampoline(SB),NOSPLIT,$0-0