When the cgo directives are parsed, any occurrence of the string ${SRCDIR}
will be replaced by the absolute path to the directory containing the source
file. This allows pre-compiled static libraries to be included in the package
directory and linked properly.
For example if package foo is in the directory /go/src/foo:

	// #cgo LDFLAGS: -L${SRCDIR}/libs -lfoo

Will be expanded to:

	// #cgo LDFLAGS: -L/go/src/foo/libs -lfoo

	dw, err := w.Create("dir/")
	if err != nil {
		t.Fatal(err)
	}
	if _, err := dw.Write(nil); err != nil {
		t.Errorf("Write(nil) to directory: got %v, want nil", err)
	}
	if _, err := dw.Write([]byte("hello")); err == nil {
		t.Error(`Write("hello") to directory: got nil error, want non-nil`)
	}
}

func TestWriterDirAttributes(t *testing.T) {
	var buf bytes.Buffer
	w := NewWriter(&buf)

	TypeLink    = '1' // Hard link
	TypeSymlink = '2' // Symbolic link
	TypeChar    = '3' // Character device node
	TypeBlock   = '4' // Block device node
	TypeDir     = '5' // Directory
	TypeFifo    = '6' // FIFO node

	// Type '7' is reserved.
	TypeCont = '7'

	// Type 'x' is used by the PAX format to store key-value records that
	// are only relevant to the next file.

	d.dirRecordsThisDisk = b.uint64() // total number of entries in the central directory on this disk
	d.directoryRecords = b.uint64()   // total number of entries in the central directory
	d.directorySize = b.uint64()      // size of the central directory
	d.directoryOffset = b.uint64()    // offset of start of central directory with respect to the starting disk number

	return nil

There is no plan to remove any of these settings.

### Go 1.19

Go 1.19 made it an error for path lookups to resolve to binaries in the current directory,
controlled by the [`execerrdot` setting](/pkg/os/exec#hdr-Executables_in_the_current_directory).
There is no plan to remove this setting.

### Go 1.18

Go 1.18 removed support for SHA1 in most X.509 certificates,

	// Name is the name of the file.
	//
	// It must be a relative path, not start with a drive letter (such as "C:"),
	// and must use forward slashes instead of back slashes. A trailing slash
	// indicates that this file is a directory and should have no data.
	Name string

	// Comment is any arbitrary user-defined string shorter than 64KiB.
	Comment string

	// NonUTF8 indicates that Name and Comment are not encoded in UTF-8.
	//

To see what instructions are defined for a given machine, say ARM,
look in the source for the <code>obj</code> support library for
that architecture, located in the directory <code>src/cmd/internal/obj/arm</code>.
In that directory is a file <code>a.out.go</code>; it contains
a long list of constants starting with <code>A</code>, like this:
</p>

<pre>
const (
	AAND = obj.ABaseARM + obj.A_ARCHSPECIFIC + iota

	}
	t.Parallel()
	// gen returns a func that writes a zip with a wantLen bytes
	// of central directory.
	gen := func(wantLen int64) func(*Writer) {
		return func(w *Writer) {
			w.testHookCloseSizeOffset = func(size, off uint64) {
				if size != uint64(wantLen) {
					t.Errorf("Close central directory size = %d; want %d", size, wantLen)
				}
			}

			uint16string := strings.Repeat(".", uint16max)

	tw.curr = &regFileWriter{tw.w, size}
	tw.pad = blockPadding(size)
	return nil
}

// AddFS adds the files from fs.FS to the archive.
// It walks the directory tree starting at the root of the filesystem
// adding each file to the tar archive while maintaining the directory structure.
func (tw *Writer) AddFS(fsys fs.FS) error {
	return fs.WalkDir(fsys, ".", func(name string, d fs.DirEntry, err error) error {
		if err != nil {

		b.uint64(records)                // total number of entries in the central directory on this disk
		b.uint64(records)                // total number of entries in the central directory
		b.uint64(size)                   // size of the central directory
		b.uint64(offset)                 // offset of start of central directory with respect to the starting disk number