type span struct {
		start int
		end   int
	}
	spans := make([]span, 0, 32)

	// Find the field start and end indices.
	// Doing this in a separate pass (rather than slicing the string s
	// and collecting the result substrings right away) is significantly
	// more efficient, possibly due to cache effects.
	start := -1 // valid span start if >= 0
	for i := 0; i < len(s); {
		size := 1

// the type:
//
//	Slice: The size specifies the length. The capacity of the slice is
//	equal to its length. A second integer argument may be provided to
//	specify a different capacity; it must be no smaller than the
//	length. For example, make([]int, 0, 10) allocates an underlying array
//	of size 10 and returns a slice of length 0 and capacity 10 that is
//	backed by this underlying array.

		return "", "", false
	}
	return name[:i], name[i+1:], true
}

// Write writes to the current file in the tar archive.
// Write returns the error [ErrWriteTooLong] if more than
// Header.Size bytes are written after [Writer.WriteHeader].
//
// Calling Write on special types like [TypeLink], [TypeSymlink], [TypeChar],
// [TypeBlock], [TypeDir], and [TypeFifo] returns (0, [ErrWriteTooLong]) regardless

	//
	// While this format is compatible with most tar readers,
	// the format has several limitations making it unsuitable for some usages.
	// Most notably, it cannot support sparse files, files larger than 8GiB,
	// filenames larger than 256 characters, and non-ASCII filenames.
	//
	// Reference:
	//	http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_92_13_06
	FormatUSTAR

says `go` `1.20`, then the program defaults to `panicnil=1`,
matching Go 1.20 instead of Go 1.21.

Because this method of setting GODEBUG defaults was introduced only in Go 1.21,
programs listing versions of Go earlier than Go 1.20 are configured to match Go 1.20,
not the older version.

To override these defaults, a main package's source files
can include one or more `//go:debug` directives at the top of the file

	instructions["JGE"] = x86.AJGE  /* greater than or equal (signed) (SF = OF) */
	instructions["JGT"] = x86.AJGT  /* greater than (signed) (ZF = 0 && SF = OF) */
	instructions["JHI"] = x86.AJHI  /* higher (unsigned) (CF = 0 && ZF = 0) */
	instructions["JHS"] = x86.AJCC  /* alternate */
	instructions["JL"] = x86.AJLT   /* alternate */
	instructions["JLE"] = x86.AJLE  /* less than or equal (signed) (ZF = 1 || SF != OF) */

	// 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.
	//
	// By specification, the only other encoding permitted should be CP-437,

except it uses <code>MOVQ</code> rather than <code>MOVL</code>:
</p>

<pre>
get_tls(CX)
MOVQ	g(CX), AX     // Move g into AX.
MOVQ	g_m(AX), BX   // Move g.m into BX.
</pre>

<p>
Register <code>BP</code> is callee-save.
The assembler automatically inserts <code>BP</code> save/restore when frame size is larger than zero.
Using <code>BP</code> as a general purpose register is allowed,

		s.err = err
	}
}

// Buffer sets the initial buffer to use when scanning
// and the maximum size of buffer that may be allocated during scanning.
// The maximum token size must be less than the larger of max and cap(buf).
// If max <= cap(buf), [Scanner.Scan] will use this buffer only and do no allocation.
//
// By default, [Scanner.Scan] uses an internal buffer and sets the

		generated output.
	-gccgo
		Generate output for the gccgo compiler rather than the
		gc compiler.
	-gccgoprefix prefix
		The -fgo-prefix option to be used with gccgo.
	-gccgopkgpath path
		The -fgo-pkgpath option to be used with gccgo.
	-gccgo_define_cgoincomplete
		Define cgo.Incomplete locally rather than importing it from
		the "runtime/cgo" package. Used for old gccgo versions.
	-godefs