addr = s.Value
		} else if s.Name == end {
			eaddr = s.Value
		}
		if addr != 0 && eaddr != 0 {
			break
		}
	}
	if addr == 0 || eaddr < addr {
		return nil
	}
	size := eaddr - addr
	data := make([]byte, size)
	for _, prog := range f.elf.Progs {
		if prog.Vaddr <= addr && addr+size-1 <= prog.Vaddr+prog.Filesz-1 {
			if _, err := prog.ReadAt(data, int64(addr-prog.Vaddr)); err != nil {
				return nil

		offset := sect.Vaddr - Segtext.Vaddr + Segtext.Fileoff
		// Handle text sections with Codeblk
		if sect.Name == ".text" {
			writeParallel(&wg, f, ctxt, offset, sect.Vaddr, sect.Length)
		} else {
			writeParallel(&wg, datblk, ctxt, offset, sect.Vaddr, sect.Length)
		}
	}

	if Segrodata.Filelen > 0 {
		writeParallel(&wg, datblk, ctxt, Segrodata.Fileoff, Segrodata.Vaddr, Segrodata.Filelen)
	}

		// address where the first byte of the segment is loaded
		// (loadSegment.Vaddr). A file offset fx maps to a virtual (symbol) address
		// sx = fx - loadSegment.Off + loadSegment.Vaddr.
		//
		// Thus, a runtime virtual address x maps to a symbol address
		// sx = x - start + offset - loadSegment.Off + loadSegment.Vaddr.
		return start - offset + loadSegment.Off - loadSegment.Vaddr, nil
	}

			f(ctxt, s)
		}
		addr += int64(len(P))
		siz := ldr.SymSize(s)
		if addr < val+siz {
			out.WriteStringPad("", int(val+siz-addr), pad)
			addr = val + siz
		}
		if addr != val+siz {
			ldr.Errorf(s, "phase error: addr=%#x value+size=%#x", addr, val+siz)
			errorexit()
		}
		if val+siz >= eaddr {
			break
		}
	}

	if addr < eaddr {

		msect.align++
	}
	msect.addr = sect.Vaddr
	msect.size = sect.Length

	if sect.Vaddr < sect.Seg.Vaddr+sect.Seg.Filelen {
		// data in file
		if sect.Length > sect.Seg.Vaddr+sect.Seg.Filelen-sect.Vaddr {
			Errorf(nil, "macho cannot represent section %s crossing data and bss", sect.Name)
		}
		msect.off = uint32(sect.Seg.Fileoff + sect.Vaddr - sect.Seg.Vaddr)
	} else {
		msect.off = 0

				}
			}
		}
	} else if m, err2 := macho.Open(src); err2 == nil {
		for _, sec := range m.Sections {
			vaddr := sec.Addr
			paddr := uint64(sec.Offset)
			size := sec.Size
			for a := range virtualEdits {
				if a >= vaddr && a < vaddr+size {
					physicalEdits[paddr+(a-vaddr)] = true
				}
			}
		}
	} else {
		t.Log(err)
		t.Log(err2)
		t.Fatal("executable format not elf or macho")
	}

type Segment struct {
	Rwx      uint8  // permission as usual unix bits (5 = r-x etc)
	Vaddr    uint64 // virtual address
	Length   uint64 // length in memory
	Fileoff  uint64 // file offset
	Filelen  uint64 // length on disk
	Sections []*Section
}

type Section struct {
	Rwx     uint8
	Extnum  int16
	Align   int32
	Name    string
	Vaddr   uint64
	Length  uint64
	Seg     *Segment
	Elfsect interface{} // an *ld.ElfShdr

		ph.Flags |= elf.PF_X
	}
	ph.Vaddr = seg.Vaddr
	ph.Paddr = seg.Vaddr
	ph.Memsz = seg.Length
	ph.Off = seg.Fileoff
	ph.Filesz = seg.Filelen
	ph.Align = uint64(*FlagRound)

	return ph
}

func elfphrelro(seg *sym.Segment) {
	ph := newElfPhdr()
	ph.Type = elf.PT_GNU_RELRO
	ph.Flags = elf.PF_R
	ph.Vaddr = seg.Vaddr
	ph.Paddr = seg.Vaddr
	ph.Memsz = seg.Length

			if i == j || sjh.Flags&SHF_ALLOC == 0 || sjh.Type == SHT_NOBITS ||
				sih.Addr == sjh.Addr && sih.Size == 0 {
				continue
			}
			if sih.Addr >= sjh.Addr && sih.Addr < sjh.Addr+sjh.Size {
				t.Errorf("ld produced ELF with section address %s within %s: 0x%x <= 0x%x..0x%x < 0x%x",
					sih.Name, sjh.Name, sjh.Addr, sih.Addr, sih.Addr+sih.Size, sjh.Addr+sjh.Size)
			}
		}
	}
}

		// If main section has no bits, nothing to relocate.
		if sect.Vaddr >= sect.Seg.Vaddr+sect.Seg.Filelen {
			return 0
		}
		sect.Reloff = uint64(ctxt.Out.Offset())
		for i, s := range syms {
			if !ldr.AttrReachable(s) {
				continue
			}
			if uint64(ldr.SymValue(s)) >= sect.Vaddr {
				syms = syms[i:]
				break
			}
		}
		eaddr := int64(sect.Vaddr + sect.Length)
		for _, s := range syms {