building gcc 7 (head) from repository on macos sierra? - c++

I have homebrew gcc 6 installed, but would like to play with gcc 7 on my mac running sierra. However, instead of the simple configure make that worked in the past, things have changed so much with sierra that I no longer can figure out, how to get gcc compiling itself. I understand that what I checked out from the repo is not supposed to work, but at least I should be able to compile it. The current roadblock is that there is no longer a /usr/include with the system headers and I didn't find the option to point configure/make to use the XCode.app internal one that apperently my homebrew gcc6 knows about.
What is the option to provide to configure to set the directory for system includes (and may be libraries) to get a current gcc compile on macos Sierra?

You need to install the "Xcode command line tools" from the app store.
That installs an assembler and linker, and the headers in /usr/include/, and then the GCC build works as expected.

Related

Can't build and run in C++ Codeblocks

So I just recently downloaded a C++ IDE called Code::Blocks and made a new project. But when I tried to Build and Run it, the code gave some errors. I know that it isn't a problem with syntax or anything like that because I ran the default code that Code::Blocks provided. The error is the following:
Project/Target: "firstcpp - Debug":
The compiler's setup (GNU GCC Compiler) is invalid, so Code::Blocks cannot find/run the compiler.
Probably the toolchain path within the compiler options is not setup correctly?!
Do you have a compiler installed?
Goto "Settings->Compiler...->Global compiler settings->GNU GCC Compiler->Toolchain executables" and fix the compiler's setup.
Tried to run compiler executable 'C:\MinGW/bin/gcc.exe', but failed!
Skipping...
Nothing to be done (all items are up-to-date).
It seems to me like there is some kind of issue with the C++ compiler, but I thought Code::Blocks already came with a C++ compiler, so I'm not too sure what the issue here. I also followed their instructions to go to Settings->Compiler...->Global compiler settings->GNU GCC Compiler->Toolchain executables, but I'm not too sure what they mean by fix the compiler. Here is a screenshot of what I'm seeing:
Also here's info on my PC if you need it:
At this point I'm not too sure what to do to fix this problem. I have asked my friends about this problem(they have already successfully downloaded and used Code::Blocks), and they said that they never encountered this problem while they were installing it.
You need to ensure that you have a working installation of the GNU Compiler Collection, and that the paths you select for your toolchain exist.
If you don't already have GCC Installed, the easiest way would be to download a Code::Blocks distribution that comes pre-bundled with MinGW from the download site. However, it's also possible for you to install GCC through other means, such as:
Installing GCC with MinGW through msys2, or
Installing GCC with scoop install gcc on Windows
In either case, you need to select the installation path that contains the bin directory when setting up the toolchain in Code::Blocks.
In case you didn't notice, C::B formed the path to compiler with both "\" back slashes and "/" slashes, which simply isn't a valid Windows path !!
Slashes are used in Linux not Windows! But for some reason C::B is not getting this. And probably your Mingw is well set !!
C:\MinGW/bin/gcc.exe should be C:\MinGW\bin\gcc.exe
I had pretty hard time trying to fix this in win 7 32 bit/C::B version 20.03 but with no success, i checked all available options and settings, and actually i started to think that it's a bug.

How to run g++-6 on debian 10, need to compile older buildroot system (Cross compiling)

How to run g++-6 on debian 10, need to compile older buildroot files.(NCurves(host-ncurses-5.9) is crashing)
I have tried to patch the files in the buildroot but it like walking into a swamp.
Fixing one problem to find the next problem.
Tried compiling 6.3 compiler from source but this is crashing with the latest gcc-8 compiler.
Any suggestions? (I always assumed that older compilers should compile with newer compilers)
My other options are:
* Running virtual machine (VM or docker) with Debian Jessie
* Compile an older compiler with a docker GCC compiler.(No idea if this works)
* maybe turn off the compiling of the local files in buildroot? (Could not find any info on this)
There is a gcc-6 package available in Debian. So you just need to sudo apt install gcc-6. link
No reason to compile gcc from source unless you need a very specific version, but even then Docker is the far easier solution since gcc has an official repo on Docker Hub. I'd also double check that you have the proper ncurses dev library installed.
The overall best solution is to containerize the correct build environment (compiler, libraries, etc.), though. It ensures you'll always be able to build the product, especially if a re-factor is not viable.

OpenMP on Mac not working anymore

I had OpenMP compiling and executing in C/C++ on my Mac but then I formatted and reinstalled a fresh copy of OS X. I believe the only difference in the setup was that I had Xcode 5 before the format, and now I have Xcode 6.
Now I get fatal error: 'omp.h' file not found
I read this has something to do with clang and gcc, but, my confusion lies with why did it work before and now its not working?
After some research I seem to have found an answer.
GCC included in the latest version of Xcode (Xcode 6) is only a symbolic link to clang. Since clang does not support OpenMP at this time, you need to install a different version of GCC. The easiest way to do this would be to use Homebrew or MacPorts.
Keep in mind that even when you do this you will probably need to alter your $PATH to have /usr/local come before /usr/bin. This is because Homebrew will have placed your newly installed GCC in /usr/local. Also, some implementations may name the command gcc-49 instead of plain gcc.
Mac OSX uses clang.The gcc compiler in OS X does not support OpenMP. To use this feature a new gcc compiler needs to be installed.
Go to Terminal, if you have not installed Hombrew, install it:
/usr/bin/ruby -e "$(curl -fsSL https://`enter code here`raw.githubusercontent.com/Homebrew/install/master/install)"
then install new version of gcc
brew reinstall gcc --without-multilib
This will not make changes to the existing gcc compiler installed by Xcode as we are reinstalling it.
After running the command given below compile the files using the new version of gcc using the syntax : gcc-version -fopenmp filename.c
To find the version type gcc and then press tab. This will list out all the possible variants of gcc. The version number can be found out from this. For example : gcc-6, gcc-4.9,etc

How to build and install GCC on Windows 7, ver. 4.8.1

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.

How do I install g++ on MacOS X?

I want to compile C++ code on MacOS X, using the g++ compiler. How do I install it?
That's the compiler that comes with Apple's XCode tools package. They've hacked on it a little, but basically it's just g++.
You can download XCode for free (well, mostly, you do have to sign up to become an ADC member, but that's free too) here: http://developer.apple.com/technology/xcode.html
Edit 2013-01-25: This answer was correct in 2010. It needs an update.
While XCode tools still has a command-line C++ compiler, In recent versions of OS X (I think 10.7 and later) have switched to clang/llvm (mostly because Apple wants all the benefits of Open Source without having to contribute back and clang is BSD licensed). Secondly, I think all you have to do to install XCode is to download it from the App store. I'm pretty sure it's free there.
So, in order to get g++ you'll have to use something like homebrew (seemingly the current way to install Open Source software on the Mac (though homebrew has a lot of caveats surrounding installing gcc using it)), fink (basically Debian's apt system for OS X/Darwin), or MacPorts (Basically, OpenBSDs ports system for OS X/Darwin) to get it.
Fink definitely has the right packages. On 2016-12-26, it had gcc 5 and gcc 6 packages.
I'm less familiar with how MacPorts works, though some initial cursory investigation indicates they have the relevant packages as well.
Installing XCode requires:
Enrolling on the Apple website (not fun)
Downloading a 4.7G installer
To install g++ *WITHOUT* having to download the MASSIVE 4.7G xCode install, try this package:
https://github.com/kennethreitz/osx-gcc-installer
The DMG files linked on that page are ~270M and much quicker to install. This was perfect for me, getting homebrew up and running with a minimum of hassle.
The github project itself is basically a script that repackages just the critical chunks of xCode for distribution. In order to run that script and build the DMG files, you'd need to already have an XCode install, which would kind of defeat the point, so the pre-built DMG files are hosted on the project page.
Type g++(or make) on terminal.
This will prompt for you to install the developer tools, if they are missing.
Also the size will be very less when compared to xcode
Download Xcode, which is free with an ADC online membership (also free):
http://developer.apple.com/technology/xcode.html
xcode is now available for free from the app store. Just "buy it" (for free) and it will download. To get the command line tools go into preferences/downloads and "install command line compiler tools".
Instead of gcc you are using clang, but it works the same.
Here is how to do it on the newer mac chips and how to switch from clang(default) to g++
Install g++ through home-brew.
Check out the version you just installed, probably 12th or higher
You can make a symbolic link from g++-12 to g++
In order to do it, just type in your terminal:
sudo ln -s $(which g++-12) /usr/local/bin/g++.
Now open a new terminal and check your version again and you should see g++ instead of clang
g++ --version