`obj2yaml` does not seem to preserve dependency information for ELF shared libraries

[SahilPatidar]

When converting an ELF shared library (.so) to YAML using obj2yaml and then back to a .so using yaml2obj, the NEEDED entries do not appear to be preserved as expected. Instead of the shared library names, the output shows numeric values.

I am not sure if this is the intended behavior or a missing feature/bug.

Steps:

# Original .so has dependencies:
0x0000000000000001 (NEEDED)             Shared library: [libA.so]
0x0000000000000001 (NEEDED)             Shared library: [libB.so]
0x0000000000000001 (NEEDED)             Shared library: [libD.so]
0x0000000000000001 (NEEDED)             Shared library: [libZ.so]

# Convert original .so → yaml → new .so
obj2yaml original.so > lib.yaml
yaml2obj lib.yaml > new.so

# New .so shows:
# readelf -d libC.so | grep NEEDED
0x0000000000000001 (NEEDED)             0x6e
0x0000000000000001 (NEEDED)             0x76
0x0000000000000001 (NEEDED)             0x7e
0x0000000000000001 (NEEDED)             0x86

Environment:

• Host: macOS (Apple M1)
• Running inside Docker:

docker run --platform=linux/amd64 -it --rm -v $(pwd):/workspace ubuntu:22.04

• LLVM version: 22.0.0git (built inside Docker)

Library Build : https://gist.github.com/SahilPatidar/00a46afc5e3168b992c6e51974c9853d

Is this the expected behavior for obj2yaml/yaml2obj with ELF?

[vgvassilev]

Is NEEDED part of the yaml file. Can you attach it?

[SahilPatidar]

This is part of a YAML file:

    Entries:
      - Tag:             DT_NEEDED
        Value:           0x6E
      - Tag:             DT_NEEDED
        Value:           0x76
      - Tag:             DT_NEEDED
        Value:           0x7E
      - Tag:             DT_NEEDED
        Value:           0x86
      - Tag:             DT_RUNPATH
        Value:           0x8E

[SahilPatidar]

See:
Original .so:

  [     1]  __gmon_start__
  [    10]  _ITM_deregisterTMCloneTable
  [    2c]  _ITM_registerTMCloneTable
  [    46]  __cxa_finalize
  [    55]  sayC
  [    5a]  sayA
  [    5f]  sayB
  [    64]  sayD
  [    69]  sayZ
  [    6e]  libA.so
  [    76]  libB.so
  [    7e]  libD.so
  [    86]  libZ.so
  [    8e]  $ORIGIN/../A:$ORIGIN/../B:$ORIGIN/../D:$ORIGIN/../Z

Yaml -> .so:

String dump of section '.dynstr':
  [     1]  __cxa_finalize
  [    10]  _ITM_deregisterTMCloneTable
  [    2c]  _ITM_registerTMCloneTable
  [    46]  __gmon_start__
  [    55]  sayZ
  [    5a]  sayD
  [    5f]  sayC
  [    64]  sayB
  [    69]  sayA