[llvm] [gold] Use ld.bfd for tests (PR #130981)

[Paul Osmialowski via llvm-commits]

pawosm-arm wrote:

Hello @nikic, I think I need some help here. How should I build LLVM on Ubuntu26.04 after this? Now when I run the tests, I can see this:

```
23:51:34  llvm-lit: /workspace/src/libcxx/utils/libcxx/test/config.py:24: note: (llvm-libunwind-static.cfg.in) All available features: add-latomic-workaround, buildhost=linux, c++29, can-create-symlinks, can-test-hardening-assertions, character-conversion-warnings, clang, clang-24, clang-24.0, clang-24.0.0, diagnose-if-support, enable-benchmarks=run, gcc-style-warnings, has-fblocks, has-fconstexpr-steps, has-unix-headers, large_tests, libcpp-has-no-experimental-hardening-observe-semantic, libcpp-has-no-experimental-optional-iterator, libcpp-has-no-experimental-syncstream, libcpp-has-no-experimental-tzdb, libcpp-has-no-incomplete-pstl, linux, long_tests, objcopy-available, objective-c++, optimization=none, std-at-least-c++03, std-at-least-c++11, std-at-least-c++14, std-at-least-c++17, std-at-least-c++20, std-at-least-c++23, std-at-least-c++26, std-at-least-c++29, stdlib=libc++, stdlib=llvm-libc++, target=aarch64-unknown-linux-gnu, verify-support
23:51:34  llvm-lit: /workspace/src/llvm/utils/lit/lit/TestingConfig.py:168: fatal: unable to parse config file '/workspace/src/llvm/test/lit.cfg.py', traceback: Traceback (most recent call last):
23:51:34    File "/workspace/src/llvm/utils/lit/lit/TestingConfig.py", line 157, in load_from_path
23:51:34      exec(compile(data, path, "exec"), cfg_globals, None)
23:51:34      ~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
23:51:34    File "/workspace/src/llvm/test/lit.cfg.py", line 695, in <module>
23:51:34      if have_ld_plugin_support(config.gold_executable, "GNU gold"):
23:51:34         ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
23:51:34    File "/workspace/src/llvm/test/lit.cfg.py", line 659, in have_ld_plugin_support
23:51:34      ld_cmd = subprocess.Popen(
23:51:34          [ld_executable, "--help"], stdout=subprocess.PIPE, env={"LANG": "C"}
23:51:34      )
23:51:34    File "/usr/lib/python3.14/subprocess.py", line 1039, in __init__
23:51:34      self._execute_child(args, executable, preexec_fn, close_fds,
23:51:34      ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
23:51:34                          pass_fds, cwd, env,
23:51:34                          ^^^^^^^^^^^^^^^^^^^
23:51:34      ...<5 lines>...
23:51:34                          gid, gids, uid, umask,
23:51:34                          ^^^^^^^^^^^^^^^^^^^^^^
23:51:34                          start_new_session, process_group)
23:51:34                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
23:51:34    File "/usr/lib/python3.14/subprocess.py", line 1990, in _execute_child
23:51:34      raise child_exception_type(errno_num, err_msg, err_filename)
23:51:34  FileNotFoundError: [Errno 2] No such file or directory: 'GOLD_EXECUTABLE-NOTFOUND'
23:51:34  
23:51:34  FAILED: CMakeFiles/check-all /workspace/build/stage/bootstrap_compiler/CMakeFiles/check-all 
```

Is there any new CMake flag that would say 'no, the system is too new, there is no GOLD'?


https://github.com/llvm/llvm-project/pull/130981