isAmount := true // Amount is zero by default
	ext := ""
	if p.peek() == lex.LSH {
		// (Rn)(Rm<<2), the shifted offset register.
		ext = "LSL"
	} else {
		// (Rn)(Rm.UXTW<1), the extended offset register.
		// Rm.UXTW<<3, the extended register.
		p.get('.')
		tok := p.next()
		ext = tok.String()
	}
	if p.peek() == lex.LSH {
		// parses left shift amount applied after extension: <<Amount
		p.get(lex.LSH)

			return false // Negative values are never okay
		case cur.Offset > math.MaxInt64-cur.Length:
			return false // Integer overflow with large length
		case cur.endOffset() > size:
			return false // Region extends beyond the actual size
		case pre.endOffset() > cur.Offset:
			return false // Regions cannot overlap and must be in order
		}
		pre = cur
	}
	return true
}

Linking

Once the _cgo_export.c and *.cgo2.c files have been compiled with gcc,
they need to be linked into the final binary, along with the libraries
they might depend on (in the case of puts, stdio). cmd/link has been
extended to understand basic ELF files, but it does not understand ELF
in the full complexity that modern C libraries embrace, so it cannot
in general generate direct references to the system libraries.

	// If Modified is set, this takes precedence over MS-DOS timestamp fields.
	if !fh.Modified.IsZero() {
		// Contrary to the FileHeader.SetModTime method, we intentionally
		// do not convert to UTC, because we assume the user intends to encode
		// the date using the specified timezone. A user may want this control
		// because many legacy ZIP readers interpret the timestamp according
		// to the local timezone.
		//

				if strings.HasSuffix(hdr.Name, "/") {
					hdr.Typeflag = TypeDir // Legacy archives use trailing slash for directories
				} else {
					hdr.Typeflag = TypeReg
				}
			}

			// The extended headers may have updated the size.
			// Thus, setup the regFileReader again after merging PAX headers.
			if err := tr.handleRegularFile(hdr); err != nil {
				return nil, err
			}

	}

	if !complete {
		// The method set has unexported methods, so all the
		// implementations are provided by the same package,
		// so the method set can be extended. Instead of recording
		// the full set of names (below), record only that there were
		// unexported methods. (If the interface shrinks, we will notice
		// because a method signature emitted during the last loop