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HDF5 and VS2012

HDF5 is my latest computing fad. I think it's definitely the best way to handle file I/O, and I'm using it in several projects. Most recently, I've been working to use it with QSTEM, which is my first real C++ project that I've used HDF5 in. The pre-built binaries are only available for VS2010 at the moment, so I've needed to rebuild HDF5 for VS2012.

There are directions for this here:
www.hdfgroup.org/HDF5/release/cmakebuild.html

They don't work. Not for me, anyway. I had several issues:

1. I did not have svn installed on my system. Digging in the install log pointed this out to me. After installing TortoiseSVN, and making sure to enable its console tools, the ctest instructions got further. Things still didn't work though. MSBuild complained about an out-of-date project file that I needed to open in the GUI.
2. I could have built SZip and ZLib separately and done a more traditional CMake build, but ZLib would not cooperate. I got some linker errors that I didn't understand, and that Google turned up nothing on.

What I discovered is that after step 1 ran to completion, it had left me with a decent CMake cache of settings. I ran the cmake gui and disabled Fortran, but kept everything else. I could now open the solution file output by CMake, and everything (including ZLib) was happy.

To save future travelers time, binaries for x64 are here:
http://t3hmikez0r.com/static/qstem/
Win 32 had problems with SZip and ZLib, even with the setup that worked for x64. Some issue with the "generator" - something going wrong with CMake. If you need 32-bit HDF5 built, sorry.

Newer

CMake and HDF5 revisited

Thanks to JC of Kitware at SciPy 2014, the situation with CMake and HDF5 on windows has greatly improved.

First, there's been a new release of HDF5 (1.8.13). This release removes a buggy CMake library finder (targets) file. The improperly generated file in HDF5 1.8.12 was thehdf5-targets-release.cmake file. Go get the new release now: http://www.hdfgroup.org/HDF5/release/obtain5.html

Secondly, there is a bug in CMake's builtin script for finding HDF5. On Windows, it finds a DLL before the Lib file, and won't link properly (http://public.kitware.com/Bug/view.php?id=14111). Thanks to JC, I understand that the way forward is not to patch that file, but ratherto move towards removing CMake's builtin scripts entirely, and push the responsibility of finding these libraries out to the library authors. Several library authors have already done this (including HDF5, thankfully). The included FindSomething.cmake scripts should be treated as a legacy, fallback approach. CMake has a great option for forcing the use of the library's scripts for defining libraries and headers. When calling the find_package function, you need to specify the NO_MODULE argument, like so:

FIND_PACKAGE(HDF5 "1.8.5" REQUIRED NO_MODULE)

This bypasses much of CMake's internal FindHDF5 script, and instead goes looking for hdf5-config.cmake in several locations, ideally finding it in the place we installed the HDF5 libraries. The new version of the HDF5 libraries now properly tells CMake where to find everything, and life is peachy.

 

In summary, use NO_MODULE when the library you're using provides a -config.cmake file. It will likely be better (more current) than CMake's internal Findsomething.cmake file. However, be careful! If not all platforms actually provide this file, then your build will break where this file does not exist. Notably, Ubuntu does not (currently) ship the hdf5-config.cmake files with the libhdf5-dev package. So, you'll need a code section like this (based onhttps://github.com/commontk/CTK/blob/master/Utilities/CMake/FindDCMTK.cmake):

# back up any user-defined HDF5_DIR setting
set(_SAVED_HDF5_DIR ${HDF5_DIR})
FIND_PACKAGE(HDF5 "1.8.5" NO_MODULE) # First look for hdf5-config.cmake in defined locations. This file is generated by HDF5 team and is likely more up to date than FindHDF5.cmake included in CMake.
IF(NOT HDF5_FOUND)
 # didn't find hdf5-config.cmake. Need to fall back on CMake's built-in FindHDF5.cmake logic.
 # required says we fail if it isn't found.
 # Restore the value reset by the previous call to 'find_package(HDF5 "1.8.5" NO_MODULE)'
 set(HDF5_DIR ${_SAVED_HDF5_DIR} CACHE PATH "HDF5 install dir" FORCE)
 FIND_PACKAGE(HDF5 "1.8.5" REQUIRED)
ENDIF()

 

More information:
details on find_package: http://www.cmake.org/cmake/help/v3.0/command/find_package.html?highlight=find_package
Creating your own package descriptions to make includes and libraries easy for downstream users:

http://www.cmake.org/Wiki/CMake/Tutorials/How_to_create_a_ProjectConfig.cmake_file
and
http://www.cmake.org/cmake/help/git-master/manual/cmake-packages.7.html#creating-packages

Thanks again to JC for helping me figure this stuff out - now I need to get QSTEM using it!