golang/go · error

read descsize failed: %v

Error message

read descsize failed: %v

What it means

Returned after successfully reading namesize when binary.Read of the descsize field fails (non-EOF). The ELF note header is namesize(4) + descsize(4) + type(4); failing on the second word means the section ended prematurely between fields. Wrapped and propagated from the note reader.

Source

Thrown at src/cmd/internal/buildid/note.go:51

	}
	defer f.Close()
	for _, sect := range f.Sections {
		if sect.Type != elf.SHT_NOTE {
			continue
		}
		r := sect.Open()
		for {
			var namesize, descsize, noteType int32
			err = binary.Read(r, f.ByteOrder, &namesize)
			if err != nil {
				if err == io.EOF {
					break
				}
				return nil, fmt.Errorf("read namesize failed: %v", err)
			}
			err = binary.Read(r, f.ByteOrder, &descsize)
			if err != nil {
				return nil, fmt.Errorf("read descsize failed: %v", err)
			}
			err = binary.Read(r, f.ByteOrder, &noteType)
			if err != nil {
				return nil, fmt.Errorf("read type failed: %v", err)
			}
			noteName, err := readAligned4(r, namesize)
			if err != nil {
				return nil, fmt.Errorf("read name failed: %v", err)
			}
			desc, err := readAligned4(r, descsize)
			if err != nil {
				return nil, fmt.Errorf("read desc failed: %v", err)
			}
			if name == string(noteName) && typ == noteType {
				return desc, nil
			}
		}
	}

View on GitHub (pinned to b6b368adc5)

Solutions

1. Rebuild the binary from source.
2. Clean the build cache: `go clean -cache`.
3. Check the binary was completely written (size, checksums, `file <bin>`).
4. Avoid stripping or post-processing the binary with tools that truncate note sections.

if _, err := buildid.ReadFile(bin); err != nil {
    if strings.Contains(err.Error(), "read descsize failed") {
        return rebuild(bin) // truncated ELF note header
    }
    return err
}

When it happens

Trigger: Reading an ELF note section whose header is at least 4 bytes but fewer than 8, so namesize parses but descsize does not. Produced by the same code path as error 1227 when corruption lands mid-header.

Common situations: Truncated ELF note sections in partially linked or partially downloaded Go binaries; corrupt object cache entries; hand-modified binaries.

Related errors

• read namesize failed: %v
• read type failed: %v
• read name failed: %v
• read desc failed: %v
• cannot find __text section

AI-assisted analysis of golang/go@b6b368adc5 (2026-08-12). Data as JSON: /api/errors/1e302bce0dd8f528. Report an issue: GitHub.