I have XCode installed (Version 7.2.1 (7C1002)) in Yosemite and have downloaded and installed command line tools. When I try to check the gcc version I get:
$ gcc -v
Segmentation fault: 11
$
The output for:
$ type -a gcc
gcc is /usr/local/bin/gcc
gcc is /usr/bin/gcc
$
From what I understand, that should mean that I have it installed so I still don't understand why I can't check it's version. Since I will need gcc for other applications I would like to have it fixed...any suggestions? Do I need to link it somehow?
You have a faulty third-party version of gcc (or perhaps another compiler masquerading as gcc) installed in /usr/local. This may be something put there by Homebrew or maybe you installed this build of gcc yourself or something.
A short-term fix would be to modify your PATH environment variable so that /usr/bin comes before /usr/local/bin. Or, you could just always specify the full path to gcc, such as /usr/bin/gcc -v.
Longer term, you probably want to remove the broken gcc that's been installed to /usr/local. How you do that exactly depends on how you originally installed it there.
Related
Mac 10.13.6 High Sierra here. New to C development and I'm trying to get myself setup with the latest stable/recommended GCC version, which I believe (keep me honest here) is 10.2.
When I go to the terminal to see what I have installed:
$ gcc --version
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 9.1.0 (clang-902.0.39.1)
Target: x86_64-apple-darwin17.7.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
$ gcc -dumpversion
4.2.1
OK...surprised to see LLVM/clang-related stuff in the output. So I try this:
$ clang --version
Apple LLVM version 9.1.0 (clang-902.0.39.1)
Target: x86_64-apple-darwin17.7.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
So its almost as if... I have both clang and gcc installed, but my clang installation has assimilated my GCC installation?! Why else would the gcc --version output reference clang?
Is this typical for Mac setups?
What do I need to do to get GCC 10.2 properly installed on my machine?
Here are some simple truths, statements and observations to try and explain what's going on:
Apple ships the clang/LLVM compiler with macOS. Clang is a "front-end" that can parse C, C++ and Objective-C down to something that LLVM (referred to as a "back-end") can compile
Clang/LLVM is located in /Applications/Xcode.app/somewhere
Apple also ships a /usr/bin/gcc which just runs clang. I have no idea why they do that - it doesn't seem very helpful to me - but they don't answer my questions
Apple puts its binaries (programs) in /usr/bin. That is an integral part of macOS and you should never touch or change anything in there - you are asking for problems if you do. This warning applies to Python too.
If you want the real, lovely GNU Compiler Collection (GCC) which includes the gcc, g++ and gfortran compilers, your best bet, IMHO, is to get them from homebrew. I will not put the installation instructions here because they could become outdated, so you should use the ones on the homebrew site.
Once you have homebrew installed, you can install the GNU Compiler Collection (GCC) with:
brew install gcc
After that, you will have all the lovely GNU Compiler Collection (GCC) of tools in /usr/local/bin, so you should put that in your PATH, near the beginning, and in any case before /usr/bin, using:
export PATH=/usr/local/bin:$PATH
In general, you should also add a similar line into your login profile, or into the system login profile, so it is set up every time you or any other user logs in.
Let's take a look:
ls /usr/local/bin/gcc* /usr/local/bin/g++*
/usr/local/bin/gcc-10
/usr/local/bin/g++-10
Depending on the versions and updates, you will then have these programs available:
gcc-10 # the real GNU C compiler
g++-10 # the real GNU C++compiler
gfortran # GNU fortran compiler
And you can check their versions with:
gcc-10 -v
g++-10 -v
gfortran -v
Now you know about homebrew, here are some more simple truths and observations:
folks (who are not the supplier of the operating system) who supply binaries (programs) for you should put their stuff in /usr/local to show that it is just a locally installed program rather than a part of the core macOS operating system
homebrew is well-behaved and installs its binaries (programs) in /usr/local/Cellar and then usually makes symbolic links from /usr/local/bin/PROGRAM to the Cellar. None of this interferes with Apple-supplied stuff.
if you want to run the homebrew version of a command, you should have /usr/local/bin first on your PATH
Let's have a look at those symbolic links:
ls -l /usr/local/bin/g*10
lrwxr-xr-x 1 mark admin 31 21 Aug 16:41 /usr/local/bin/g++-10 -> ../Cellar/gcc/10.2.0/bin/g++-10
lrwxr-xr-x 1 mark admin 31 21 Aug 16:41 /usr/local/bin/gcc-10 -> ../Cellar/gcc/10.2.0/bin/gcc-10
If you want to know what you are actually running when you enter a command, use the type command like this.
type gcc
gcc is hashed (/usr/bin/gcc)
That tells you that if you run gcc you will actually be running /usr/bin/gcc which we know is from Apple - because it is in /usr/bin
Now try this:
type gcc-10
gcc-10 is hashed (/usr/local/bin/gcc-10)
That tells you that if you run gcc-10 you will actually be running /usr/local/bin/gcc-10 which we know is from homebrew - because it is in /usr/local/bin
I am trying to build GraphChi on OS X Yosemite but get the following error:
fatal error: 'omp.h' file not found
From this question - How to include omp.h in OS X? - I learned that Yosemite uses Clang instead of gcc, which does not include omp.h.
$ which gcc
/usr/bin/gcc
$ gcc -v
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 6.0 (clang-600.0.56) (based on LLVM 3.5svn)
Target: x86_64-apple-darwin14.1.0
Thread model: posix
Next, I installed gcc via Homebrew
$ brew info gcc
gcc: stable 4.9.2 (bottled)
http://gcc.gnu.org
/usr/local/Cellar/gcc/4.9.2_1 (1092 files, 177M)
Built from source with: --without-multilib
and updated $PATH to include the path to the new gcc version
$ echo $PATH
/usr/local/Cellar/gcc/4.9.2_1:usr/local/bin:/opt/local/bin:/opt/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin
however, gcc -v and which gcc still point to the old version, and building GraphChi still doesn't work due to the missing omp.h file
Does anyone know what else I need to do?
Update
locate omp.h returned:
/usr/local/Cellar/apple-gcc42/4.2.1-5666.3/lib/gcc/i686-apple-darwin11/4.2.1/include/omp.h
/usr/local/Cellar/gcc/4.9.2_1/lib/gcc/4.9/gcc/x86_64-apple-darwin14.1.0/4.9.2/include/omp.h
/usr/local/Cellar/gfortran/4.8.2/gfortran/lib/gcc/x86_64-apple-darwin13.0.0/4.8.2/include/omp.h
my ~/.profile:
export PATH=/usr/local/Cellar/gcc/4.9.2_1/lib/gcc/4.9/gcc/x86_64-apple-darwin14.1.0/4.9.2/include:/usr/local/Cellar/gcc/4.9.2_1/bin:usr/local/bin:/opt/local/bin:/opt/local/sbin:$PATH
I solved this with installing gcc with homebrew:
brew install gcc --without-multilib
and then building the source code with
CC=gcc-5 CXX=g++-5 cmake ..
CC=gcc-5 CXX=g++-5 make -j7
Once you have installed gcc-4.9 with homebrew, it will automatically be in your path. To use OpenMP, you just need to make sure you are using the newly installed gcc-4.9, and it will be able to find omp.h.
In the case of GraphChi, you will have to go change line 3 of the Makefile to be gcc-4.9. From there, running make should just work. They describe this in their README, but at least the version they describe is out of date https://github.com/GraphChi/graphchi-cpp#problems-compiling-on-mac.
clang does not support OpenMP yet. Also gcc by default links to Apple's LLVM clang compiler (not the GCC installed from brew).
Instead gcc-4.9 would link to GCC. I think if -fopenmp is specified omp.h is included automatically.
It is possible to manually build a version of clang with OpenMP support, see http://clang-omp.github.io
You shouldn't add the include path to PATH; instead, specify it as CFLAGS, including the -I option. You can export the CFLAGS variable, or set it on the fly.
Depending on how you compile things, you could do
CFLAGS=-I/usr/local/Cellar/gcc/4.9.2_1/lib/gcc/4.9/gcc/x86_64-apple-darwin14.1.0/4.9.2/include/omp.h gcc <whatever>
Of course, in this case you can specify it directly on the gcc command (as -I/usr/local/....), but the CFLAGS variable also works with configure (as configure often won't have an option to specify where it should look for specific include files); probably with make, or even for those installing a Python package: CFLAGS=-I... pip install <some-package>.
Other flags to consider are
CXXFLAGS: C++ specific pre-processor flags
LDFLAGS: linker specific flags (e.g. LDFLAGS=-L/some/path/... for linking with dynamic libraries).
CC: specify the C compiler to use. This is an easy way to avoid the built-in gcc alias for clang on OS X. Just use CC=/usr/local/bin/gcc-4 make or similar.
CXX: specify the C++ compiler to use.
I somehow lost the man pages for gcc and g++. I'm not sure where/what to look for. I'm pretty sure the man pages used to work some time ago. It also works on my Mac at work where I use roughly the same setup. Could it be a problem with brew? Or is it a bug in the XCode Command Line Tools?
Update: I just tried to re-install the XCode Command Line Tools. No luck.
~
✓ man gcc
No manual entry for gcc
~
✗ which gcc
/usr/bin/gcc
~
✓ gcc --version
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn)
Target: x86_64-apple-darwin13.1.0
Thread model: posix
gcc isn't installed anymore by Xcode, it really installs clang and calls it gcc
usxxplayegm1:~ grady$ which gcc
/usr/bin/gcc
usxxplayegm1:~ grady$ /usr/bin/gcc --version
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 5.1 (clang-503.0.38) (based on LLVM 3.4svn)
Target: x86_64-apple-darwin13.0.2
Thread model: posix
you need man clang
I thought it was a symlink, but ls -l doesn't list it as a symlink, so either it is a hard link or some other sort of trickery.
This may be old and doesn't quite answers your concrete question, but I found myself in the same problem with Kali Linux and I solved it with this command, maybe is useful for someone:
apt install gcc-doc
Look at how you set MANPATH in your .profile. Instead of, e.g.,
export MANPATH=/opt/local/man:/usr/local/man
you should do
export MANPATH="/opt/local/man:/usr/local/man:$MANPATH"
And then (breathe) open a new Terminal window.
This way your .profile isn't wiping out (or reflecting an old version of) the system's way of setting MANPATH, which is modified when you install (or reinstall) Xcode.
I use High Sierra with g++ 7.2 port. Setting MANPATH environment to /opt/local/man (or to /opt/local/man/man1 where g++.gz is found) did not work. So, after ensuring that the soft link g++.gz points to g++-mp-7.1.gz (there was not a g++-mp-7.2.gz in the man1 directory though g++7.2 is my version), I always use the command:
man /opt/local/share/man/man1/g++.gz
that never fails. You can store an alias for this in your .profile, if you are frequently using the man command for g++.
For anyone who stumbles upon this currently (like I did), I found that I needed to locate my version of gcc (which I had installed with brew). This is annoying when gcc --version gives the clang version instead! To find the correct gcc version, run
$ ls /usr/local/opt/gcc/bin | grep gcc
gcc-10
gcc-ar-10
gcc-nm-10
...
So I had gcc-10. Whenever you wish to use gcc just replace it with gcc-10, e.g. man gcc-10. Of course you could write an alias for gcc to gcc-10, but this probably is not a great idea, as Xcode seems to rely on the gcc --> clang (hard?) link.
I've recently installed gcc 4.6.3 on my MAC (with OSX Lion, XCode 4.3, gcc 4.2.1). I've made a folder named my_gcc463, which contains all files after compiling gcc with make command, etc.
I've also installed MacPorts to select between all versions of gcc that I have. The problem is when I run this command:
port select --list gcc
I can't see the new gcc 4.6.3 in the list so that I can select that. Also when I run this command:
sudo ln -s -f ~/my_gcc463/gcc-4.6.3 /usr/bin/gcc
to link gcc to the one I want, It's not working. For example after creating that symlink, when I run:
gcc -v
It doesn't give me the version. What should I do to make my new gcc appear in the gcc list? Did I do anything wrong? Should I install it in other way?
Thank you in advance for helping me. :)
port select is a tool to maintain the gcc installations from MacPorts and, if available, the versions provided by Apple. Although you could hack it up by dropping your own descriptions into /opt/local/etc/select/gcc, I would recommend a different approach for this.
To achieve what you want you should modify your PATH environment variable to include the new path to your gcc version at the front, such that gcc resolved to the correct absolute path.
Assuming your new gcc binary is at ~/my_gcc463/gcc, you should add the following to your .profile/.bash_profile or .bashrc:
export PATH=~/my_gcc463:$PATH
After setting this up, run gcc -v in a new terminal window to check if it is working as expected.
I have a problem concerning libstdc++.so.
I installed a new version of gcc and tried to compile C++ code. The compiling worked, but when I try to execute the binary (m5.opt is its name) I've got the following error:
build/ALPHA_SE/m5.opt: /usr/lib64/libstdc++.so.6: version `GLIBCXX_3.4.9' not found (required by build/ALPHA_SE/m5.opt).
Do I need to replace libstdc++.so? And if so, where can I download the version I want? On the GCC-website they say libstdc++ is a part of gcc now.
Details
GCC:
I had gcc 4.1.2 before, but I downloaded gcc 4.2.4. From the untarred gcc-directory I executed ./configure; make; sudo make install`.
When I tried to use gcc or g++ to compile, it's default version was still 4.1.2. To overcome this I replaced some links:
mv /usr/bin/gcc /usr/bin/gcc_bak
ln -s /usr/local/bin/gcc gcc
mv /usr/bin/g++ /usr/bin/g++_bak
ln -s /usr/local/bin/g++ g++
GLIBC(++) -- libstdc++:
/usr/lib64/libstdc++.so.6 -> libstdc++.so.6.0.8
/usr/local/lib/libstdc++.so -> libstdc++.so.6.0.9
/lib/libc.so.6 -> libc-2.5.so -> libc-2.5.so
Linux-version:
uname -a gives:
Linux madmax 2.6.18-128.4.1.el5 #1 SMP Tue Aug 4 12:51:10 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux
The problem is that you built your new GCC incorrectly: on Linux you should use
./configure --prefix=/usr
The default installation prefix is /usr/local, which is why make install put gcc and g++ binaries into /usr/local/bin, etc.
What's happening to you now is that you compile and link using the new (symlinked) GCC 4.2.4, but at runtime your program binds to the old /usr/lib64/libstdc++.so.6 (version 6.0.8, instead of required 6.0.9). You can confirm that by running ldd build/ALPHA_SE/m5.opt: you should see that it uses /usr/lib64/libstdc++.so.6.
There are several fixes you could do.
env LD_LIBRARY_PATH=/usr/local/lib64 ldd build/ALPHA_SE/m5.opt
should show you that setting LD_LIBRARY_PATH is sufficient to redirect the binary to correct library, and
LD_LIBRARY_PATH=/usr/local/lib64 build/ALPHA_SE/m5.opt
should just run. You could "bake" this path into m5.opt binary by relinking it with -Wl,-rpath=/usr/local/lib64.
A more permanent solution is to fix the libraries the same way you fixed the binaries:
cd /usr/lib64 && mv libstdc++.so.6 libstdc++.so.6_bak &&
ln -s /usr/local/lib64/libstdc++.so.6 .
An even better solution is to reconfigure the new GCC with --prefix=/usr, and then make all install.
I know this is a very old question, but ...
It's not usually a good idea to replace the system compiler (i.e. the one in /usr) because the entire system will have been built with it and depend on it.
It's usually better to install the new compiler to a separate location and then see the libstdc++ FAQ How do I insure that the dynamically linked library will be found? and Finding Dynamic or Shared Libraries in the manual for how to ensure the correct libstdc++.so is found at runtime.
The other answers here should be fine, but the 'quick and easy' solution if you do happen to have gcc installed to /usr/local/ is to just add the new libs to the LD_LIBRARY_PATH
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib64
You can also check the to see if you have the right versions of GLIBC installed using
strings /usr/lib/libstdc++.so.6 | grep GLIBC
strings /usr/local/lib64/libstdc++.so.18 | grep GLIBC
I got this last tip from another forum so credits due where credits due!