fix xdmf build issues in build_visit

[aowen87]

Rick Angelini ran into several issues. In summary... For some reason, Xdmf builds its library(s) in a 'bin' dir instead of a 'lib' dir. Its probably cosmetic but lets check that out bv_xdmf doesn't set LIBXML2_LIBRARY variable name quite right. Its missing the :FILEPATH qualifier. That may create problems when Xdmf build tries to find the libxml2 library in our VTK insallation XDMF_SYSTEM_LIBXML2 setting? What should it be. I think it should be set to OFF and we should be using libxml2 in VTK, as the other variables we define appear to be trying to do that. However, examining Xdmf's CMakeList.txt file suggests that SYSTEM may have a different interpretation there. XDMF_SYSTEM_LIBZ should be adjusted to either be YES or to be NO and instead use whatever ZLIB build_visit has installed (and definitely not vtk's zlib as per #2679)

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Ticket number: 2688
Status: Resolved
Project: VisIt
Tracker: Bug
Priority: Normal
Subject: fix xdmf build issues in build_visit
Assigned to: Kathleen Biagas
Category: -
Target version: 2.12.0
Author: Mark Miller
Start: 10/13/2016
Due date:
% Done: 0%
Estimated time:
Created: 10/13/2016 04:08 pm
Updated: 10/25/2016 08:13 pm
Likelihood: 3 - Occasional
Severity: 2 - Minor Irritation
Found in version: 2.10.0
Impact:
Expected Use:
OS: All
Support Group: Any
Description:
Rick Angelini ran into several issues. In summary... For some reason, Xdmf builds its library(s) in a 'bin' dir instead of a 'lib' dir. Its probably cosmetic but lets check that out bv_xdmf doesn't set LIBXML2_LIBRARY variable name quite right. Its missing the :FILEPATH qualifier. That may create problems when Xdmf build tries to find the libxml2 library in our VTK insallation XDMF_SYSTEM_LIBXML2 setting? What should it be. I think it should be set to OFF and we should be using libxml2 in VTK, as the other variables we define appear to be trying to do that. However, examining Xdmf's CMakeList.txt file suggests that SYSTEM may have a different interpretation there. XDMF_SYSTEM_LIBZ should be adjusted to either be YES or to be NO and instead use whatever ZLIB build_visit has installed (and definitely not vtk's zlib as per #2679)

Comments:
Re #1: Looks like the .so's are placed in 'bin' during build, but are installed to 'lib'. It's controlled by XDMF's root CMakeLists.txt file, where this is defined:SET (LIBRARY_OUTPUT_PATH ${Xdmf_BINARY_DIR}/bin/ CACHE PATH "Single output directory for building all libraries.")Since the Xdmf library we currently use will soon be updated, I think we can safely ignore this for now.#2, #3 done.#4, should be handled by #2679.