How to use H5Version.hpp.in to access HIGHFIVE_VERSION_* definitions

[Schellenberg3]

I've cloned HighFive and have been using it with my project. For my project, it would be nice to track group creation order but it is not required. Since this feature was added in 2.7.0 I would like something like this:

HighFive::GroupCreateProps properties{};

#if HIGHFIVE_VERSION_MAJOR > 2 && HIGHFIVE_VERSION_MINOR > 7
properties.add(HighFive::LinkCreationOrder(HighFive::CreationOrder::Tracked | HighFive::CreationOrder::Indexed));
#endif

auto sensor_record_group = metrics_group.createGroup("SensorRecord", properties);

So we only try to compile the features if the correct version is available.

I see that these definitions exist in the file H5Version.hpp.in but I am unfamiliar with how the file is formatted:

HighFive/include/highfive/H5Version.hpp.in

Lines 11 to 13 in be68bd0

	#define HIGHFIVE_VERSION_MAJOR @PROJECT_VERSION_MAJOR@
	#define HIGHFIVE_VERSION_MINOR @PROJECT_VERSION_MINOR@
	#define HIGHFIVE_VERSION_PATCH @PROJECT_VERSION_PATCH@

From this Stack Overflow question it seems like the files *.in extension and @...@ formatting is related to autoconf.

Could anyone provide some guidance on how to properly use this file?

For context, I have HighFive as a submodule for my project and am developing on a Windows machine.

[1uc]

The *.in file and @...@ templating syntax is related to CMake. As a user of HighFive H5Version.hpp.in is interesting because something (cmake) will create a file H5Version.hpp. Essentially, user code should do:

#include <highfive/H5Version.hpp>

// ...

HighFive::GroupCreateProps properties{};

#if HIGHFIVE_VERSION_MAJOR > 2 && HIGHFIVE_VERSION_MINOR > 7
properties.add(HighFive::LinkCreationOrder(HighFive::CreationOrder::Tracked | HighFive::CreationOrder::Indexed));
#endif

auto sensor_record_group = metrics_group.createGroup("SensorRecord", properties);

I'd suggest you first try if you're lucky and just include the above file and use the macros HIGHFIVE_VERSION_{MAJOR,MINOR,PATCH}.

If that doesn't work the most likely reason is that the file hasn't been generated (e.g. if your project doesn't use CMake or doesn't have a add_subdirectory(highfive)). Alternatively, it might have been generated, but because it's generated in the build directory of HighFive a -I${HIGHFIVE_BUILD_DIR} might be missing (e.g. because your project doesn't use the HighFive CMake target). If you're in this case, please describe in a little bit more detail how you're using HighFive. I think the important questions are:

1. Do you use CMake?
2. If yes, do you use add_subdirectory and or the CMake target HighFive?
3. If no, do you install HighFive (cmake -D ... -B build . && cmake --build build && cmake --install build) or use the sources directly?

[Schellenberg3]

Thanks for the response, Luc!

I am using CMake in my project. From my file, the lines relevant to HighFive are:

set(HIGHFIVE_UNIT_TESTS OFF CACHE BOOL "Enable unit tests(requires Catch2 to be present)")
set(HIGHFIVE_BUILD_DOCS OFF CACHE BOOL "Enable documentation building")
set(HIGHFIVE_EXAMPLES   OFF CACHE BOOL "Compile examples")

add_subdirectory(${BASE_DIR}/deps/HighFive)
set(HIGHFIVE_INCLUDE_DIRS ${PROJECT_SOURCE_DIR}/deps/HighFive/include)

# Other packages imports with find_package...

include_directories(
    # Other includes ...
    ${HIGHFIVE_INCLUDE_DIRS}
)

CMake is still new to me so I would not be surprised if I am making a simple mistake!

Looking at the CMakeLists.txt in HighFive's root I see where the line where CMake should be generating this file:

HighFive/CMakeLists.txt

Lines 10 to 11 in be68bd0

	configure_file(${CMAKE_CURRENT_SOURCE_DIR}/include/highfive/H5Version.hpp.in
	${CMAKE_CURRENT_BINARY_DIR}/include/highfive/H5Version.hpp)

However, when I build my project, the *.hpp.in file is not turned into the expected *.hpp file.

I don't need the unit tests, docs, or examples but could setting those flags off have impacted something?

[1uc]

The first three lines are good, you don't need any of that. (You might want to also remove Boost support; we can do that later.)

The line

add_subdirectory(${BASE_DIR}/deps/HighFive)

should trigger the configure_file. (Unrelated: check the BASE_DIR it should probably be some CMAKE_*_DIR.) The add_subdirectory should also make the target HighFive available. You'd use it as follows

add_executable(runme ...)
target_link_libraries(runme PUBLIC HighFive)

add_library(linkme ...)
target_link_libraries(linkme [PRIVATE,PUBLIC] HighFive)

Please remove ${HIGHFIVE_INCLUDE_DIRS} from:

include_directories(
    # Other includes ...
    ${HIGHFIVE_INCLUDE_DIRS}
)

Generally, this isn't modern cmake; and the "modern" is what makes cmake much more agreeable. Personally, I like this reference (and references therein):

https://cliutils.gitlab.io/modern-cmake/chapters/basics.html

Now, you should check the compile commands:

cmake --build build --verbose

It should include something vaguely like:

/usr/bin/c++ ... -I${YOUR_INCLUDE_PATHS} -I deps/HighFive/include -I build/.../deps/HighFive/include -isystem /usr/include/hdf5/serial -O2 -g -DNDEBUG -std=c++11 -fPIC  ...

The salient point being that there's two include paths for HighFive, one is simply the directory where the code resides, the other is a subdirectory of the build directory (which is where you should find H5Version.hpp).

[Schellenberg3]

This was exactly the issue! It seems there was something with my misuse of CMake.

I updated my project's CMakeLists.txt to utilize target_link_libraries. I also turned off boost, as you suggested, and make some other, improvements suggested in the introduction of Modern CMake. Somewhere along the way, the configure_file line was properly activated.

Running the cmake --build build --verbose command I did see the two include paths you highlighted and found the H5Version.hpp file within the build directory. My code is including this correctly now!

Thank you for the assistance and for providing a great resource for learning about CMake!