shrink-rpath renames global variable symbol name

[jtojnar]

patchelf --shrink-rpath renames global variable symbol breaking DeaDBeeF’s wildmidi plug-in.

This is the variable in question:

https://github.com/DeaDBeeF-Player/deadbeef/blob/7ac83fb204fc3c8a35486ef8f9550cd98cec674e/plugins/wildmidi/src/wildmidi_lib.c#L399

Compare the patched and unpatched libraries:

$ nm -A -D -l result/wildmidi-patched.so | grep wildmidi_lib.c:399
result/wildmidi-patched.so:000000000001f2a0 B X	/build/source/plugins/wildmidi/src/wildmidi_lib.c:399
$ nm -A -D -l result/wildmidi.so | grep wildmidi_lib.c:399
result/wildmidi.so:000000000001f2a0 B b	/build/source/plugins/wildmidi/src/wildmidi_lib.c:399

Here is the reproducible:

with import <nixpkgs> { };
with pkgs;

let
  deadbeef = fetchFromGitHub {
    owner = "DeaDBeeF-Player";
    repo = "deadbeef";
    rev = "1.8.0";
    sha256 = "126i5qlkpv7pvi1mmc9y0jhqs6jjspsj7j615n2ddvsb2jsps81c";
  };

in runCommand "patchelf" {
    buildInputs = [ patchelf gcc ];
  } ''
    cp -r ${deadbeef} source
    chmod -R u+w -- source
    cd source/plugins/wildmidi
    gcc -ggdb -shared -Iinclude -DWILDMIDI_VERSION=\"0.2.2\" -DWILDMIDILIB_VERSION=\"0.2.2\" -DTIMIDITY_CFG=\"/etc/timidity.conf\" -fPIC wildmidiplug.c src/wildmidi_lib.c include/wildmidi_lib.h -o wildmidi.so -lm

    mkdir $out
    cp wildmidi.so $out/wildmidi-patched.so
    cp wildmidi.so $out/wildmidi.so
    patchelf --shrink-rpath $out/wildmidi-patched.so
  ''

[jtojnar]

Likely the same issue as #45

[solna86]

It does indeed look like #45, which arises for example in several Rpackages like Seurat. It'd be good to see if there are any similarities to narrow down what causes patchelf to output wrong binaries.

[domenkozar]

@jtojnar could you try again with master (or patchelfUnstable in nixpkgs)?

[jtojnar]

Can still reproduce with /nix/store/xlkfqvahjpd2cm7kysy1g43gcw9pjgja-patchelf-2020-06-03 on NixOS/nixpkgs@fd9d37e:

with import ./. { };
with pkgs;

let
  deadbeef = fetchFromGitHub {
    owner = "DeaDBeeF-Player";
    repo = "deadbeef";
    rev = "1.8.0";
    sha256 = "126i5qlkpv7pvi1mmc9y0jhqs6jjspsj7j615n2ddvsb2jsps81c";
  };

in runCommand "patchelf" {
    buildInputs = [ patchelfUnstable gcc ];
  } ''
    cp -r ${deadbeef} source
    chmod -R u+w -- source
    cd source/plugins/wildmidi
    gcc -ggdb -shared -Iinclude -DWILDMIDI_VERSION=\"0.2.2\" -DWILDMIDILIB_VERSION=\"0.2.2\" -DTIMIDITY_CFG=\"/etc/timidity.conf\" -fPIC wildmidiplug.c src/wildmidi_lib.c include/wildmidi_lib.h -o wildmidi.so -lm

    mkdir $out
    cp wildmidi.so $out/wildmidi-patched.so
    cp wildmidi.so $out/wildmidi.so
    patchelf --shrink-rpath $out/wildmidi-patched.so

    echo "These should be the same:"
    nm -A -D -l $out/wildmidi.so | grep wildmidi_lib.c:399
    nm -A -D -l $out/wildmidi-patched.so | grep wildmidi_lib.c:399
    echo "^ The symbol should not have been renamed to X."
  ''

[domenkozar]

It would be helpful if you can also try 0.9 as the linked issue says it used to work.

[jtojnar]

I originally reproduced this with 0.9. Just tried it again to be sure and replacing patchelfUnstable by patchelf in the example above indeed does not fix the issue.