commentLen:         b.uint16(),
	}
	l := int(d.commentLen)
	if l > len(b) {
		return nil, 0, errors.New("zip: invalid comment length")
	}
	d.comment = string(b[:l])

	// These values mean that the file can be a zip64 file
	if d.directoryRecords == 0xffff || d.directorySize == 0xffff || d.directoryOffset == 0xffffffff {
		p, err := findDirectory64End(r, directoryEndOffset)
		if err == nil && p >= 0 {

-extldflags='-ggdb -O3'. If any package in a build includes a .cc or
other file compiled by the C++ compiler, the go tool will use the
-extld option to set the host linker to the C++ compiler.

These defaults mean that Go-aware build systems can ignore the linking
changes and keep running plain 'cmd/link' and get reasonable results, but
they can also control the linking details if desired.