How can I cross compile libSSL as a dynamic librairy? - dll

Does anybody knows how can I cross compile libSSL as a dynamic librairy using openWRT toolchain?
Thanks for your answers and have a nice day

Openwrt already provides libssl in packages, simply take feeds update and select openssl in make menuconfig, then compile the openwrt build.

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Parallel STL algorithms requiring tbb or not?

I remember that g++ 9.3.0 required to link against libtbb to use parallel STL algorithms, otherwise it gave compilation errors. I have a docker container using an ubuntu image where I have installed g++-10 only and I can use the algorithms without writing -ltbb. How can I explain this? I searched everywhere and there is no libtbb anywhere, so I am assuming g++-10 no longer needs it? Where can I read some documentation about this fact that it does not need it or is required up to version x.x.x? Thanks for clarifying.

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.

GNUStep make problems

I have installed the GNUStep gnustep-msys-system-0.29.0-setup.exe and gnustep-core-0.29.1-setup.exe on my WinXp Machine
I am able to compile problems. The documentation says that gnustep-core comes with the make utility but I am unable to locate it or use it !!
Assuming everything is installed correctly, jacekmigacz's answer may work.
However, an easier path might be to simply install Linux. That will give you the ability to trivially install GNUStep and LLVM.
Alternatively, grab the GNUStep Live CD (http://wiki.gnustep.org/index.php/GNUstep_Live_CD).
cd gnustep/core/make
./configure
make
make install

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!

how to build g++

I'm currently trying to get g++ working, and looking at http://gcc.gnu.org/install/build.html, I can't seem to find where it says how "to perform a 3-stage bootstrap of the compiler". Where would I find this information?
(I'm on a mac, in case that matters.)
After running configure, you do make bootstrap
You cannot bootstrap GCC without an already-functioning compiler on your platform:
From the prerequisites page:
ISO C90 compiler
Necessary to bootstrap GCC, although versions of GCC prior to 3.4 also allow bootstrapping with a traditional (K&R) C compiler.
And to preempt your next question, you also need a functioning compiler (usually GCC) in order to build Clang+LLVM.
It might be possible to do what you're trying so hard to do, by cross-compiling GCC from some other platform (see this section of the documentation). But I imagine this is not for the feint of heart, and you'd be far, far better off simply updating your copy of Mac OS X to the latest version with Xcode support.
From that link:
For a native build, the default configuration is to perform a 3-stage bootstrap of the compiler when `make' is invoked.
It seems to me that if your configuration isn't tweaked, it should do it out of the box. Just type make.
More specifically, you have to download the source code, and follow the instructions in that whole tutorial in order to build.
A side note - I am finding it hard to believe that there is no easy way to get GCC on an OSX box without having the installation media. That sounds really annoying :)
Edit:
If you are simply trying to write C++ on OSX, you could install one of many other IDEs. If you are lucky, they may come with their own compiler. Here is a list of alternatives to XCode:
http://alternativeto.net/desktop/xcode/?profile=mac&platform=mac