cmake find_package full list of installed modules - cmake

Where, or how, can I get the full list of packages supported by find_package?
I understand those are modules, so they must reside somewhere?
I'm building on online automated packaging system for C++/ROS, and I need to have a detailed list of what is available (as package).

Here is a complete guide for it.

Related

Problem building GNURadio in custom environment

I am trying to build the latest GNURadio package on my development system. Unfortunately this system configuration is tightly controlled and I can't just install new packages of software on it as it is used to develop a product and all development systems are kept in lockstep. We are currently on an older version of RedHat.
While I cannot modify the system includes I can download and use newer versions of packages locally (in non-system directories) as long as that doesn't affect the product build/debug environment. Normally this isn't a problem.
However, when building GNURadio I found that our development platforms use an older version of the Boost libraries than is required to build GNURadio. So, I got the latest version of Boost and extracted it into my local (home) directory. I found several directions for, I thought, instructing CMake to use additional include directories. Unfortunately, this hasn't seemed to work with the Boost libraries. CMake keeps complaining that it finds the older version of Boost and not the newer one I have extracted locally.
I have tried using
-DCMAKE_CXX_STANDARD_INCLUDE_DIRECTORIES=<dir>
and
-DCMAKE_CXX_STANDARD_INCLUDE_DIRECTORIES_BEFORE=<dir>
and this had no effect. I then tried adding the following to the top-level CMakeLists.txt file:
SET(CMAKE_INCLUDE_DIRECTORIES_BEFORE ON)
SET(CMAKE_CXX_STANDARD_INCLUDE_DIRECTORIES <dir>)
or, even
include_directories(BEFORE <dir>)
Again, no joy.
I did a bit of digging and found that there is a GrBoost.cmake module and it had an additional configuration for the boost directory so I added this:
list(PREPEND BOOST_LIBRARYDIR "<dir>")
to the top of the file. Again, no luck.
I've never used CMake before (and I'm not really keen on learning yet another build system if I don't have to - our company just switched to bazel and I am coming up to speed on that) so I am flying blind here.
What do I have to do to get CMake to look in my local directory to find the Boost stuff I downloaded?
Ok. As it often happens, just after asking the question I was able to find an answer.
It turns out that there is a command-line option to CMake (CMAKE_PREFIX_PATH=<dir>) where you can specify additional base paths to search for CMake config files. I just added this to the command-line and it was found just fine.
I wasn't even aware that Boost came with such config files. Live and learn.
#vre's comment would have probably worked just as well (maybe better, in fact).

Determine appropriate version for cmake_minimum_required()

From a set of CMakeLists.txt files, how can I determine an appropriate version number for cmake_minimum_required()? Is there a better way than being familiar with the history of CMake features and using trial and error?
CMake has per-version documentation on its website. Using it, you may check that all features you use in your project are supported by a specific CMake version.
Features include command names, command options and their possible values, names of modules shipped with CMake.
Usually project does not need precise minimum CMake version. You may take reasonable version, which is accessible for users, and check whether this version supports all features you use.

Can a library that uses CMake also be built with SCons?

I want to use KDL (Kinematics and Dynamics Library) in robot control box. But robot control box uses SCons as their build system while KDL uses CMake.
It turned out that the control box doesn't have CMake installed. Should I install CMake in the control box? Or write SCons file for compiling KDL?
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My question is ambiguous. Sorry for that. And unfortunately, I cannot show the link of Control Box, it's not public. Here is link of KDL installation manual.
http://www.orocos.org/kdl/installation-manual
Let me make it more clear.
Forget all of previous question above and all about Control box, KDL. Let's say that you want to use one library. But the library can be built using CMake according to installation manual. Your PC doesn't have CMake installed but it has SCons, and unfortunately you should not install CMake on your PC.
If you can only use SCons, what can you do?
I know this situation is not usual, I want to know your opinion.
To answer your initial question: Yes, you should always try to install CMake, if that is a build requirement for you library and if you need to build that library from the sources.
To answer your later question: Replacing or rewriting the build system scripts is a major effort and not advisable. In general there is no script to convert build-systems. Such script might help to make the manual transformation. If you have a look at LLVM's effort to replace Autotools by CMake or Boost replacing it's own build system by CMake, you find out it takes several people several years and still not everybody is satisfied.
Often you don't need to build the library yourself. Either there are already built packages from the project directly of from your distribution (Debian etc. packages) or third party packagers like Mac Ports or NuGet.
In your case KDL provides Debian/Ubuntu packages.
Additional KDL is part of ROS, which is experimental in Homebrew for OS X.

How to make deployable software which uses libraries that do not have apt-get options with CMake

I wrote a piece of software which works well on my own box. It has been a headache to get it onto another box, though.
The main problem is that there is a library which it uses which is not a library covered by apt-get; it's called pngwriter. And pngwriter is also very finicky, and it is not very easily installed. It also has version compatibility issues. To get around all of that, I thought it would be great to include the source for pngwriter with my project, and have CMake go ahead and make pngwriter with the rest of the code.
So my main question is: Is this type of deployment canon? Should CMake call the makefiles that the developers of the software already wrote, and then use FIND_PACKAGE locally, or will I need to rewrite all of their makefiles so that I can use ADD_LIBRARY?
I'd recommend using the ExternalProject_Add function.
The docs are OK, but there is a decent article which explains things in a bit more detail. From this article:
The ExternalProject_Add function makes it possible to say “download this project from the internet, run its configure step, build it and install it”
Bear in mind that you can skip the install step altogether, or you could choose to install to a location inside your own build directory.

Library search path for libstdc++

I have compiled shared libraries dynamically linked against libstdc++.so using GLIBCXX_3.4.11. I want to send my code to someone whose stdc++ library is only of version 3.4.10. Rather than ask him to update his library version (this is a software customer, so I can't assume they'll be willing or able to change system files) I would like to ship the appropriate version of libstdc++.so, placed in a lib folder with the directory location of my code. How do I get my own code to use the appropriate (later) version? I find that /etc/ld.so.conf includes the directory /lib64, where an offending older version of libstdc++.so resides. Setting LD_LIBRARY_PATH does not override this. This seems to deviate from the advertised behavior. Any idea why this is happening? How do I complete my rather simple task?
Thanks.
I understand that this question is old, but I found it while trying to sort out my own linking trouble which was similar. You will have to build your program against a version of libstdc++ which is compatible with your colleague's version of the library. The easiest solution, of course, is to link against his version of the library so he doesn't need to make special tweaks on his side to link your library.
To do this, you will want to install a version of GCC which can build binary compatible libraries so you can actually link against his version of libstdc++. GLIBCXX_3.4.11 is from gcc-4.4 and later, so you will need gcc-4.3. Build your program using this and you should be in good shape.
You can consult the following page for a list of library ABI compatabilities:
http://gcc.gnu.org/onlinedocs/libstdc++/manual/abi.html
You could also build an rpm/deb which requires the version of libstdc++ you already have and if it's not available, refuse to install. This gives you a bit of an interface which gives him a promise that if his system is setup with the correct dependencies, he can use your library. In that sense, it's like a loose SLA for your library in what you do and don't support.
Hope that helps!