`LD_LIBRARY_PATH=` and `LD_LIBRARY_PATH=.` do not work

[abitrolly]

I am trying to setup cibuildwheel that fails at the repair step given these two files.

# ls -la *.so.2 *whl
-rwxr-xr-x. 1 root root 1965280 Jun 21 11:29 libopendht.so.2
-rw-r--r--. 1 root root 1507129 Jun 20 10:19 opendht-2.4.5-cp36-cp36m-linux_x86_64.whl

Fails with traceback.

  INFO:auditwheel.main_repair:Repairing opendht-2.4.5-cp36-cp36m-linux_x86_64.whl
  Traceback (most recent call last):
    File "/usr/local/bin/auditwheel", line 8, in <module>
      sys.exit(main())
    File "/opt/_internal/pipx/venvs/auditwheel/lib/python3.9/site-packages/auditwheel/main.py", line 59, in main
      rval = args.func(args, p)
    File "/opt/_internal/pipx/venvs/auditwheel/lib/python3.9/site-packages/auditwheel/main_repair.py", line 161, in execute
      out_wheel = repair_wheel(
    File "/opt/_internal/pipx/venvs/auditwheel/lib/python3.9/site-packages/auditwheel/repair.py", line 74, in repair_wheel
      raise ValueError(
  ValueError: Cannot repair wheel, because required library "libopendht.so.2" could not be located

I prepended LD_LIBRARY_PATH=. to the command as instructed in #85, and still got the same message. The command became this.

LD_LIBRARY_PATH=. auditwheel repair -w /tmp/cibuildwheel/repaired_wheel /tmp/cibuildwheel/built_wheel/opendht-2.4.5-cp36-cp36m-linux_x86_64.whl

I tried LD_LIBRARY_PATH= but it didn't work too.
https://github.com/abitrolly/opendht/runs/6981236904?check_suite_focus=true
Found it strange given this piece of code.

auditwheel/src/auditwheel/lddtree.py

Lines 104 to 106 in 55bc5ee

	if ldpath == "":
	# The ldso treats "" paths as $PWD.
	ldpath = os.getcwd()

LD_LIBRARY_PATH=$PWD works fine.
https://github.com/abitrolly/opendht/runs/6987495549?check_suite_focus=true

[aganders3]

I see why this is confusing but this happens because the CWD is changed to a tmp dir with only the contents of the input wheel when entering this InWheelCtx context manager in repair.py.

I'm not sure whether this should be changed to use the LD_LIBRARY_PATH entries with respect to the original CWD, or if it should just be documented that LD_LIBRARY_PATH entries need to be absolute paths.

[abitrolly]

@aganders3 the best way is to merge #374 with the explicit --add-path option.