blob: 84d3edb664eb25534e998f54c1402dfd1cbc2418 [file] [log] [blame]
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package cgotest
// Test that we have no more than one build ID. In the past we used
// to generate a separate build ID for each package using cgo, and the
// linker concatenated them all. We don't want that--we only want
// one.
import (
"bytes"
"debug/elf"
"os"
"testing"
)
func testBuildID(t *testing.T) {
f, err := elf.Open("/proc/self/exe")
if err != nil {
if os.IsNotExist(err) {
t.Skip("no /proc/self/exe")
}
t.Fatal("opening /proc/self/exe: ", err)
}
defer f.Close()
c := 0
sections:
for i, s := range f.Sections {
if s.Type != elf.SHT_NOTE {
continue
}
d, err := s.Data()
if err != nil {
t.Logf("reading data of note section %d: %v", i, err)
continue
}
for len(d) > 0 {
// ELF standards differ as to the sizes in
// note sections. Both the GNU linker and
// gold always generate 32-bit sizes, so that
// is what we assume here.
if len(d) < 12 {
t.Logf("note section %d too short (%d < 12)", i, len(d))
continue sections
}
namesz := f.ByteOrder.Uint32(d)
descsz := f.ByteOrder.Uint32(d[4:])
typ := f.ByteOrder.Uint32(d[8:])
an := (namesz + 3) &^ 3
ad := (descsz + 3) &^ 3
if int(12+an+ad) > len(d) {
t.Logf("note section %d too short for header (%d < 12 + align(%d,4) + align(%d,4))", i, len(d), namesz, descsz)
continue sections
}
// 3 == NT_GNU_BUILD_ID
if typ == 3 && namesz == 4 && bytes.Equal(d[12:16], []byte("GNU\000")) {
c++
}
d = d[12+an+ad:]
}
}
if c > 1 {
t.Errorf("found %d build ID notes", c)
}
}