if err2 != nil {
			t.Fatal(err2)
		}

		id, err = ReadFile(tmp)
		if id != newID || err != nil {
			t.Errorf("ReadFile(%s after Rewrite) = %q, %v, want %q, nil", f, id, err, newID)
		}

		// Test an ELF PT_NOTE segment with an Align field of 0.
		// Do this by rewriting the file data.
		if strings.Contains(name, "elf") {
			// We only expect a 64-bit ELF file.
			if elf.Class(data[elf.EI_CLASS]) != elf.ELFCLASS64 {
				continue

				return desc, nil
			}
		}
	}
	return nil, nil
}

var elfGoNote = []byte("Go\x00\x00")
var elfGNUNote = []byte("GNU\x00")

// The Go build ID is stored in a note described by an ELF PT_NOTE prog
// header. The caller has already opened filename, to get f, and read
// at least 4 kB out, in data.
func readELF(name string, f *os.File, data []byte) (buildid string, err error) {

	sec = ef.Section(".note.go.buildid")
	if sec == nil {
		t.Fatalf("can't find go build id")
	}
	cnt := 0
	for _, ph := range ef.Progs {
		if ph.Type == elf.PT_NOTE {
			cnt += 1
		}
	}
	if cnt != expected {
		t.Fatalf("want %d PT_NOTE segment, got %d", expected, cnt)
	}
}

const pieSourceTemplate = `
package main

import "fmt"

	Desc []byte // Contents of the "desc" field.
	Type uint32 // Contents of the "type" field.
}

// parseNotes returns the notes from a SHT_NOTE section or PT_NOTE segment.
func parseNotes(reader io.Reader, alignment int, order binary.ByteOrder) ([]elfNote, error) {
	r := bufio.NewReader(reader)

	// padding returns the number of bytes required to pad the given size to an

		{0xcf, 0xfa, 0xed, 0xfe},
	}
)

var readSize = 32 * 1024 // changed for testing

// readBinary reads the build ID from a binary.
//
// ELF binaries store the build ID in a proper PT_NOTE section.
//
// Other binary formats are not so flexible. For those, the linker
// stores the build ID as non-instruction bytes at the very beginning
// of the text segment, which should appear near the beginning

	startva := *FlagTextAddr - int64(HEADR)
	resoff := elfreserve

	var pph *ElfPhdr
	var pnote *ElfPhdr
	getpnote := func() *ElfPhdr {
		if pnote == nil {
			pnote = newElfPhdr()
			pnote.Type = elf.PT_NOTE
			pnote.Flags = elf.PF_R
		}
		return pnote
	}
	if *flagRace && ctxt.IsNetbsd() {
		sh := elfshname(".note.netbsd.pax")
		resoff -= int64(elfnetbsdpax(sh, uint64(startva), uint64(resoff)))

			{PT_LOAD, PF_R + PF_W, 0x688, 0x600688, 0x600688, 0x210, 0x218, 0x200000},
			{PT_DYNAMIC, PF_R + PF_W, 0x6b0, 0x6006b0, 0x6006b0, 0x1a0, 0x1a0, 0x8},
			{PT_NOTE, PF_R, 0x21c, 0x40021c, 0x40021c, 0x20, 0x20, 0x4},
			{PT_LOOS + 0x474E550, PF_R, 0x5b8, 0x4005b8, 0x4005b8, 0x24, 0x24, 0x4},
			{PT_LOOS + 0x474E551, PF_R + PF_W, 0x0, 0x0, 0x0, 0x0, 0x0, 0x8},
		},

	PT_NULL    ProgType = 0 /* Unused entry. */
	PT_LOAD    ProgType = 1 /* Loadable segment. */
	PT_DYNAMIC ProgType = 2 /* Dynamic linking information segment. */
	PT_INTERP  ProgType = 3 /* Pathname of interpreter. */
	PT_NOTE    ProgType = 4 /* Auxiliary information. */
	PT_SHLIB   ProgType = 5 /* Reserved (not used). */
	PT_PHDR    ProgType = 6 /* Location of program header itself. */
	PT_TLS     ProgType = 7 /* Thread local storage segment */

		{"PT_LOOS", Const, 0},
		{"PT_LOPROC", Const, 0},
		{"PT_MIPS_ABIFLAGS", Const, 16},
		{"PT_MIPS_OPTIONS", Const, 16},
		{"PT_MIPS_REGINFO", Const, 16},
		{"PT_MIPS_RTPROC", Const, 16},
		{"PT_NOTE", Const, 0},
		{"PT_NULL", Const, 0},
		{"PT_OPENBSD_BOOTDATA", Const, 16},
		{"PT_OPENBSD_RANDOMIZE", Const, 16},
		{"PT_OPENBSD_WXNEEDED", Const, 16},
		{"PT_PAX_FLAGS", Const, 16},
		{"PT_PHDR", Const, 0},

pkg debug/elf, const PT_HIPROC ProgType
pkg debug/elf, const PT_INTERP ProgType
pkg debug/elf, const PT_LOAD ProgType
pkg debug/elf, const PT_LOOS ProgType
pkg debug/elf, const PT_LOPROC ProgType
pkg debug/elf, const PT_NOTE ProgType
pkg debug/elf, const PT_NULL ProgType
pkg debug/elf, const PT_PHDR ProgType
pkg debug/elf, const PT_SHLIB ProgType
pkg debug/elf, const PT_TLS ProgType
pkg debug/elf, const R_386_32 R_386