[PATCH] D62179: [llvm-readelf] - Allow dumping of the .dynamic section even if there is no PT_DYNAMIC header.

[Jan Kratochvil via Phabricator via llvm-commits]

jankratochvil added subscribers: kwk, jankratochvil.
jankratochvil added a comment.
Herald added a subscriber: seiya.

There is a regression - after this patch - at least after its later commit:

  commit 8ac7b2d07bd6042afe0e8618ca8682d7663f4be8
  Author: George Rimar <grimar at accesssoftek.com>
  Date:   Wed May 29 10:31:46 2019 +0000
      [llvm-readelf] - Allow dumping of the .dynamic section even if there is no PT_DYNAMIC header.
      Differential revision: https://reviews.llvm.org/D62179
      llvm-svn: 361943

llvm-readobj cannot print `.dynsym` of executable without Program Headers. GNU `readelf` can print it fine. We have found it with @kwk because of some unrelated bug in `obj2yaml`/`yaml2obj' dropping Program Headers.
On 64-bit Linux one can create a test binary with:

  cp -p /bin/bash /tmp/bashtest;dd if=/dev/zero of=/tmp/bashtest bs=1 count=2 seek=$[0x38] conv=notrunc

`llvm-readobj -dyn-symbols` formerly printed for example:

  Symbol {
    Name: tilde_expand_word (11424)
    Value: 0xDBE60

while now it prints only:

  warning: Unable to parse DT_GNU_HASH: Virtual address is not in any segment
  warning: Unable to parse DT_STRTAB: Virtual address is not in any segment
  warning: Unable to parse DT_SYMTAB: Virtual address is not in any segment
  warning: Unable to parse DT_JMPREL: Virtual address is not in any segment
  warning: Unable to parse DT_RELA: Virtual address is not in any segment
  File: /tmp/bashtest
  Format: ELF64-x86-64
  Arch: x86_64
  AddressSize: 64bit 
  LoadName:
  DynamicSymbols [
  ]


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D62179/new/

https://reviews.llvm.org/D62179