This is to help debug why curl fails sometimes when invoked from Julia on GitHub Actions
with ubuntu-latest. This follows from https://discourse.julialang.org/t/link-checking-with-github-actions-not-working/61823/4.
Answer: Importing Ipopt.jl causes the error:
curl: /opt/hostedtoolcache/julia/1.6.1/x64/bin/../lib/julia/libcurl.so.4: no version information available (required by curl)
when the curl command is invoked from Julia in the same session (see the
run).
This occurs because of different libcurl.so.x.x.x versions (one already installed and one
introduced by Julia):
/opt/hostedtoolcache/julia/1.6.1/x64/lib/julia/libcurl.so.4
/opt/hostedtoolcache/julia/1.6.1/x64/lib/julia/libcurl.so.4.7.0
/usr/lib/x86_64-linux-gnu/libcurl.so.4
/usr/lib/x86_64-linux-gnu/libcurl.so.4.6.0
/usr/local/julia1.6.1/lib/julia/libcurl.so.4
/usr/local/julia1.6.1/lib/julia/libcurl.so.4.7.0
This isn't a problem in and of itself, but it appears that Ipopt.jl uses LD_LIBRARY_PATH
which induces the weird error behavior. See https://github.com/jump-dev/Ipopt.jl/blob/5cbb08da95ddae85cb501e648aac20da97a32be1/src/Ipopt.jl#L98-L106
This problem is manifest when using linkcheck= true on Documenter.jl builds that import
Ipopt.jl in the examples. It probably also applies to other programs in addition to curl.