Im running Matlab on linux (Elementary OS)
The problem im facing is that Matlab isnt compatible with the gcc compiler higher than 4.9.
Same question as: https://www.mathworks.com/matlabcentral/answers/348906-downgrading-gcc-g-for-use-with-mex
When I use "sudo apt get install gcc" 5.4 is automatically installed. When I remove 5.4, Matlab will not recognize 4.9 which I've installed. How do I get Matlab to recognize gcc/g++ 4.9 as my compiler?
I've also followed this but it didnt resolve the problem:
https://www.mathworks.com/matlabcentral/answers/137228-setup-mex-compiler-for-r2014a-for-linux#answer_263109
Any help would be greatly appreciated.
When I remove 5.4, Matlab will not recognize 4.9 which I've installed. How do I get Matlab to recognize gcc/g++ 4.9 as my compiler?
I use Ubuntu (from which you OS is derived) and have had a similar issue. Basically, you can use update-alternative to switch between gcc versions on your choice. Here is a link that explains how to do it.
Here is the documentation on update-alternative, if you need more in-depth knowledge of its functionalities.
Note that uninstalling the default gcc for your distro (5.4 in your case) is no longer required with this solution: you can switch back to it for you development when not using Matlab. You can even install more than two versions of gcc if needed.
Hope this solves your issue.
There is no reason to downgrade GCC for MATLAB.
The reason you run into issues on Linux is because MATLAB installs its own copies of the GCC libraries. If your MEX-files expect newer libraries, they'll fail. You can delete the GCC libraries that come with MATLAB, and it will use the newer ones on your system.
The libraries are at $(MATLABROOT)/sys/os/glnx86 for 32-bit MATLAB, and $(MATLABROOT)/sys/os/glnxa64 for 64-bit MATLAB. $(MATLABROOT) is the installation root for MATLAB.
The files in question are libgcc_s.so*, libstdc++.so* and libg2c.so* (or at least they used to be called like this, I don't have a Linux MATLAB installation here to double-check).
This trick worked for MATLAB 7.0, and still worked a month ago when I suggested this to a colleague.
I do recommend that you rename or move the files, so you can replace them if things go sour.
You will need to restart MATLAB after this change, of course.
Related
I have MinGW installed on my computer and I just found out that my GCC/G++ has problems compiling newer C++ standards. So I want to upgrade from 4.8.1-4 to the latest version (5.3 at the time of writing this).
The MinGW Installation Manager doesn't install a newer version than 4.8.1-4, so I'll probably have to do it somewhat manually. But how? I heard that Cygwin might be able to do it, but I think MinGW and Cygwin would interfere with each other (environment variables). So I'd rather not do it that way.
MSYS2 might be a good answer to your needs. It has cygwin-like environment together with mingw3/mingw64 environment. And GCC version is 5.3
Link: https://msys2.github.io/
Not exactly sure where this question belongs, let me know if I should move it.
Here is the issue; over the past years I have a put together a relatively large personal codebase in C++11 that I'm using for work, but my workplace runs supposedly the latest version of RHEL on their cluster, which runs gcc 4.4.7, which supports C++11 only partially.
I have battled to get a decent compiler installed, but apparently there is no easy way of making this happen, so instead I am wondering whether it would be possible to cross-compile C++11 sources on my own desktop, and export the executable on the cluster at my workplace. I just don't know where to start in order to do that:
Is it possible (and how) to cross-compile C++11 sources from Ubuntu to RHEL?
Since I am at it, is it possible to rebuild gcc 4.8 or a suitable libstdc++ (or libc++) entirely from Ubuntu to an rpm package compatible with RHEL?
(Note: I would preferably use clang (3.4) to compile on my desktop, but gcc (4.8) would be fine too.)
I'm running CentOS 6.4 and need a later version of the C++ compiler to build my development tools (Qt Creator in this case).
I'm unclear on the implications of using devtools and I'm hoping someone can explain.
If I compile programs using devtools, does that means the executable will run on other Centos 6.4 installations without change?
Or..do I know have to ship libraries or other files with my compiled programs?
If so...do I have to modify my C++ code to reference the later libraries? or is this something done by the person installing my compiled program
I hope this somewhat late answer can still help you. What I found is that compiling my project with devtoolset (1.1 in my case, but that should not matter too much) on RHEL 6.4 produces binaries which can almost run on a standard RedHat EL 6.4 (should be similar for Centos 6.4).
The only trouble I ran into was compiling my project with -std=c++11, which produced some problems due to incompatible symbols. The reason is that the GCC folks considered these parts of the standard library to be experimental in GCC 4.4, so they broke ABI compatibility in some places.
Turns out, there's an easy fix: Link your programs with the additional command-line-argument -static-libstdc++. That way, the binary becomes a bit larger but is runs on an unmodified RHEL 6.4 without installing additional libraries/updates for the devtoolset.
To answer your questions explicitly:
Yes, almost.
No.
Don't change the code, just add -static-libstdc++ when linking.
I would like to upgrade my old GCC compiler to v. 4.8.1.
Currently I'm using Code::Blocks IDE (nightly build, svn 8982), and my compiler is GCC 4.4.1.
I downloaded fresh GCC from their site - gcc.gnu.org
From what I've read in documentation, they say that I should first build compiler by myself. Afterwards, they throw something like this:
% mkdir objdir
% cd objdir
% srcdir/configure [options] [target]
However, I completly have no idea what to do with these lines.
And even if I did, afterwards come maaany lines with some additional options, where I am even more lost then before.
I don't know if there is any easy way of installing it, but from what I've read here, I can download MSYS from MinGW and it will do everything(I hope?) for me. However, from what I see there, it says that MinGW comes with already built version of GCC, meaning I won't be able to use mine anyway. Am I right? If yes, what should I do to build and use GCC? If not, then will I be able to easily install GCC after downloading MSYS?
Thanks in advance.
I can download MSYS from MinGW
YOu can.
and it will do everything(I hope?) for me.
It won't. MSys provides environment for building software that requires unix-like environment. To be more precise - autotools. If you aren't familiar with *nix build process (configure script), Mingw won't really help you.
However, from what I see there, it says that MinGW comes with already built version of GCC,
Yes, version 4.7.2 at the moment.
meaning I won't be able to use mine anyway. Am I right?
No. If you don't add Mingw/MSys to your PATH, you can keep multiple different installations on the same machine. It also SHOULD be possible to use multiple different versions of gcc within the same installation of mingw, but things can get messy here. (gcc3 and gcc4 should be able to exist, not sure about 4.7.2 and 4.8.1)
If yes, what should I do to build and use GCC?
You should search for precompiled binaries provided by somebody else. Compiling gcc yourself is possible, but for you (i.e. if you aren't arleady familiar with msys) it might not be worth the effort.
Either you could try http://mingw-w64.sourceforge.net/ or mingw-nuwen. Mingw provided by nuwen is 32bit only, but is very easy to install. The problem is that standard mingw distribution includes update tool (with "mingw uppdate" and "mingw upgrade" you can upgrade installed packages to their latest version), bug "mingw-nuwen" doesn't have such tool.
Because you say
However, I completly have no idea what to do with these lines.
You should either use precompiled mingw provded by somebody else, or use another compiler. If you don't really need bleeding-edge C++11 support ON WINDOWS, use visual studio express.
I recently switched back to Windows7 (x64) because of perfomance issues with my graphics card on linux but i miss the abilty to easily compile open source software on Windows. I have a copy of the intel c compiler which is somewhat better than the gnu c compiler and i would like to use it to compile software written for linux.
I've already installed cygwin and managed to compile something. The 'make-install' didn't work though but that's another issue. Now my question is, how can i tell 'make' to use the windows intel compiler?
Most of the configure scripts you'll find in OSS have probably been created by the Autotools. Those should, basically, support the icc. To use it, although you may have GCC installed side-by-side, it would be necessary to set the environment variable CC to the (cygwin) path to Intel's C compiler and CXX to Intel's C++ compiler prior to running configure.
You may run into trouble with software packages that unconditionally set compiler flags that only GCC understands. I have heard, though, that, by now, icc actually implements most of these.
Update
Something similar has been asked before.