I don't think it is talking about the cpanm command line

That's right - it's talking about the perl Makefile.PL command line .... which is the command you would run if you wanted to build XML::LibXML "manually".
In that case you would cd to the top-level directory in the XML-LibXML source and run something like: 
perl Makefile.PL INC="-I/usr/include/x86_64-linux-gnu" LIBS="-L/usr/li
+b/x86_64-linux-gnu -lxml2 -lz -lm"

[download]
You would then follow that with make test then (assuming make test went satisfactorily) make install

I don't know how you'd incorporate that command line requirement into the automated cpanm procedure. (I'd just do it "manually".)

Alternatively, adding /usr/include/x86_64-linux-gnu to the CPATH environment variable and adding /usr/lib/x86_64-linux-gnu to the LIBRARY_PATH environment variable might also work - at least if you're using a gcc compiler: 
export CPATH=/usr/include/x86_64-linux-gnu:$CPATH
export LIBRARY_PATH=/usr/lib/x86_64-linux-gnu:$LIBRARY_PATH

[download]
Cheers,
Rob

In reply to Re^3: perlbrew/cpanm on 64 bit Ubuntu by syphilis
in thread perlbrew/cpanm on 64 bit Ubuntu by emgrasso

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