Installed gcc49 via homebrew, but gcc -v still shows I have gcc42? - c

When I enter
brew install gcc49
I see:
Warning: gcc49-4.9.0 already installed
and when I check my gcc version with gcc -v
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-darwin12.5.0
Thread model: posix
Is there something else I have to do besides install gcc49 via homebrew to be able to use it?

Related

Install GCC on Mac OS high sierra

I've already visited the following answer but my question is different.
Install GNU GCC on mac
Mac OS ships with Clang and somehow /usr/bin/gcc is linked to Clang tool I assume because of this line.
gcc
clang: error: no input files
Any idea on how can I install https://gcc.gnu.org/ standalone on my system?
gcc --version
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk/usr/include/c++/4.2.1
Apple LLVM version 9.0.0 (clang-900.0.38)
Target: x86_64-apple-darwin17.2.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
Any idea on how can I install https://gcc.gnu.org/ standalone on my system?
Generally speaking: Don't. That isn't a standard configuration; Clang is the recommended compiler for current macOS systems.
If you have a very good reason, you can use Homebrew to install GCC (brew install gcc). Keep in mind that it cannot be used to build native macOS applications.

Installing GCC 4.4.7 on OSX 10.10

I already have gcc version 6.1.0 installed on my computer thanks to XCode:
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 6.1.0 (clang-602.0.53) (based on LLVM 3.6.0svn)
Target: x86_64-apple-darwin15.0.0
Thread model: posix
But I need to install gcc version 4.4.7 and I have tried doing things like brew install gcc447 and such but it always says package not found. Is there a way to install gcc 4.4.7 on OSX 10.10 and have it run as "gcc4" or a similar alias while still keeping the XCode 6.1.0 version?
Homebrew doesn't have recipes for every individual minor version of GCC, only for the major versions like 4.4. Conveniently, though, 4.4.7 is the most recent version of GCC 4.4, so you're fine.
Run brew install gcc44; the compiler will be installed as gcc-4.4.

Compiling on Mac

I am brand new to this forum, and have just begun to learn C. The book I am going through wants me to compile the code that was written. I have a file "cards.c", I am on a Mac, have Xcode installed, downloaded gcc from Apple and installed it.
$ gcc -v
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 6.1.0 (clang-602.0.53) (based on LLVM 3.6.0svn)
Target: x86_64-apple-darwin14.4.0
Thread model: posix
When I type:
gcc cards.c -o cards
I get:
clang: error: no such file or directory: 'cards.c'
clang: error: no input files
I have tried going to Xcode downloads to install Xcode's Command Line Tools, it doesn't show up there, maybe I have a newer version?
I cannot figure out how to compile this, any ideas on what I am doing wrong?
Does the cards.c file need to be in a specific folder somewhere?

Linking Homebrew-compiled openmpi (or mpich2) to Homebrew's gcc

I'm new to Homebrew (I usually use Macports, but I'm trying out Homebrew on a 2nd computer), and I wish to install the openmpi (or mpich2) package. Steps are as follows (carried out on Mac OS X Yosemite with Xcode 6 installed):
brew install gcc
brew install openmpi
However, I suspect the linking may have been done incorrectly, due to the following reasons:
The symbolic link for /usr/local/bin/gcc is missing:
$ which gcc
/usr/bin/gcc
$ gcc --version
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/c++/4.2.1
Apple LLVM version 6.0 (clang-600.0.54) (based on LLVM 3.5svn)
Target: x86_64-apple-darwin14.0.0
Thread model: posix
$ which gcc-4.9
/usr/local/bin/gcc-4.9
$ gcc-4.9 --version
gcc-4.9 (Homebrew gcc 4.9.2) 4.9.2
Copyright (C) 2014 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
mpicc may have been linked to the Apple gcc:
$ which mpicc
/usr/local/bin/mpicc
$ mpicc --version
Apple LLVM version 6.0 (clang-600.0.54) (based on LLVM 3.5svn)
Target: x86_64-apple-darwin14.0.0
Thread model: posix
My questions are as follows:
How do I get the /usr/local/bin/gcc symbolic link? Or is Homebrew deliberately avoiding this for certain reasons? e.g. if Homebrew is compiling all its packages using Apple gcc, which is assumed to be in the path, would changing the path to gcc-4.9 mean that Homebrew now compiles its packages with gcc-4.9 instead?
Is the Homebrew-installed Open MPI linked to the Apple gcc (and not the Homebrew gcc)? If yes, is it possible (or advisable) to change the linking?
Alternatively, how necessary is it to fix the linkages? Could I run into certain problems if I choose not to fix it? For example, I'm considering using ln -s to forcibly create the /usr/local/bin/gcc symbolic link. But is this a good idea (*)?
(*) I understand there are likely to be issues when linking object files created by different compilers. So with (1), (2) and (3), I'm hoping to find a solution that avoids combinations whereby I'm creating object files with different compilers (some with gcc-4.9 and some with the Apple gcc).
You need to do the following:
1) Add environment variables for homebrew (you can also add these lines to your ~\.bashrc):
$ export HOMEBREW_CC=gcc-4.9
$ export HOMEBREW_CXX=g++-4.9
2) Rebuild and reinstall openmpi and its dependencies from source
$ brew reinstall openmpi --build-from-source
3) In the end you will get a message like:
==> Reinstalling open-mpi
==> Using Homebrew-provided fortran compiler.
This may be changed by setting the FC environment variable.
==> Downloading http://www.open-mpi.org/software/ompi/v1.8/downloads/openmpi-1.8.
Already downloaded: /Library/Caches/Homebrew/open-mpi-1.8.4.tar.bz2
==> ./configure --prefix=/usr/local/Cellar/open-mpi/1.8.4 --disable-silent-rules
==> make all
==> make check
==> make install
Warning: open-mpi dependency gcc was built with a different C++ standard
library (libstdc++ from clang). This may cause problems at runtime.
🍺 /usr/local/Cellar/open-mpi/1.8.4: 785 files, 23M, built in 41.2 minutes
$ mpicc --showme
gcc-4.9 -I/usr/local/Cellar/open-mpi/1.8.4/include -L/usr/local/opt/libevent/lib -L/usr/local/Cellar/open-mpi/1.8.4/lib -lmpi
On my MacBook I had some conflicts with XCode 6.2, which were solved following this instructions
If you want to install mpich
$ unlink openmpi
$ brew unlink gcc
$ brew install homebrew/versions/gcc5
$ brew install mpich --build-from-source
$ mpicc -v
mpicc for MPICH version 3.2
Using built-in specs.
COLLECT_GCC=gcc-5
COLLECT_LTO_WRAPPER=/usr/local/Cellar/gcc5/5.4.0/libexec/gcc/x86_64-apple-darwin14.5.0/5.4.0/lto-wrapper
Target: x86_64-apple-darwin14.5.0
Configured with: ../configure --build=x86_64-apple-darwin14.5.0 --prefix=/usr/local/Cellar/gcc5/5.4.0 --libdir=/usr/local/Cellar/gcc5/5.4.0/lib/gcc/5 --enable-languages=c,c++,objc,obj-c++,fortran --program-suffix=-5 --with-gmp=/usr/local/opt/gmp --with-mpfr=/usr/local/opt/mpfr --with-mpc=/usr/local/opt/libmpc --with-isl=/usr/local/opt/isl014 --with-system-zlib --enable-libstdcxx-time=yes --enable-stage1-checking --enable-checking=release --enable-lto --disable-werror --with-pkgversion='Homebrew gcc5 5.4.0' --with-bugurl=https://github.com/Homebrew/homebrew-versions/issues --enable-plugin --disable-nls --enable-multilib
Thread model: posix
gcc version 5.4.0 (Homebrew gcc5 5.4.0)
It would probably be cleaner if you simply modify the configuration file for the Open MPI compiler wrapper and make it invoke gcc-4.9 instead of simply gcc. As I have no idea where exactly Homebrew puts Open MPI and therefore cannot give you the correct path directly, you should search for it:
$ find /usr/local -name mpicc-wrapper-data.txt
Once you have found mpicc-wrapper-data.txt, find the line that starts with compiler= and modify it to read:
compiler=gcc-4.9
You should also modify all other files that match the shell glob mpi*-wrapper-data.txt and modify the compiler=... line accordingly. Use g++-4.9 in mpic++, mpicxx, and mpiCC. Use gfortran-4.9 (if installed) in mpif77 and mpif90 (for Open MPI versions < 1.8) or for mpifort (for versions >= 1.8).
Mixing object code produced by different compilers on the same platform should be fine as long as all of them adhere to the same ABI, which is more or less the case with Clang and GCC. In the end, all programs are linked against the system libraries that come with OS X and those are compiled with Clang only.

how to find gcc version on mac

I am using OS 10.9 on mac machine. I want to know the version of gcc I am using. So I tried gcc --version on terminal and it results :
$ gcc --version
Configured with: --prefix=/Applications/Xcode5-DP.app/Contents/Developer/usr --with-gxx-include-dir=/Applications/Xcode5-DP.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk/usr/include/c++/4.2.1
Apple LLVM version 5.0 (clang-500.1.58) (based on LLVM 3.3svn)
Target: x86_64-apple-darwin13.0.0
Thread model: posix
Here in output, there is no detail related to gcc but clang is there. I am confused
whether gcc command executes clang or gcc(gnu).
You seem to not actually have gcc on your path. As of recent versions of Xcode, it installs a "gcc" that is instead a link to Clang.
gcc -dumpversion | cut -f1 -d.
-dumpversion Print the compiler version (for example, 3.0) — and don't do anything else.
The same works for following compilers/aliases:
cc -dumpversion
g++ -dumpversion
clang -dumpversion
tcc -dumpversion
Be careful with automate parsing the GCC output:
Output of --version might be localized (e.g. to Russian, Chinese, etc.)
GCC might be built with option --with-gcc-major-version-only. And some distros (e.g. Fedora) are already using that
GCC might be built with option --with-pkgversion. And --version output will contain something like Android (5220042 based on r346389c) clang version 8.0.7 (it's real version string)
The tools supplied by Apple have been switched from GCC to Clang. The gcc command is linked to clang as a convenience. In OS X 10.9, you do not have GCC on your system unless you have installed it independently of Apple packages.
In case you installed gcc via brew install, it might've got installed as gcc-11.
You can run brew info gcc to get path where it is installed and get exact name of the binary by listing the directory.
$ brew info gcc
gcc: stable 11.2.0 (bottled), HEAD
GNU compiler collection
https://gcc.gnu.org/
/usr/local/Cellar/gcc/11.2.0_3 (2,163 files, 459.8MB) *
...
$ ls /usr/local/Cellar/gcc/11.2.0_3/bin
c++-11 gcc-ar-11 gcov-dump-11 gfortran x86_64-apple-darwin21-g++-11 x86_64-apple-darwin21-gcc-ranlib-11
cpp-11 gcc-nm-11 gcov-tool-11 gfortran-11 x86_64-apple-darwin21-gcc-11 x86_64-apple-darwin21-gcc-tmp
g++-11 gcc-ranlib-11 gdc lto-dump-11 x86_64-apple-darwin21-gcc-ar-11 x86_64-apple-darwin21-gdc-11
gcc-11 gcov-11 gdc-11 x86_64-apple-darwin21-c++-11 x86_64-apple-darwin21-gcc-nm-11 x86_64-apple-darwin21-gfortran-11
Then using gcc-11 -v will get you actual version of gcc installed.
$ gcc-11 -v
Using built-in specs.
COLLECT_GCC=gcc-11
COLLECT_LTO_WRAPPER=/usr/local/Cellar/gcc/11.2.0_3/bin/../libexec/gcc/x86_64-apple-darwin21/11/lto-wrapper
Target: x86_64-apple-darwin21
Configured with: ../configure --prefix=/usr/local/opt/gcc --libdir=/usr/local/opt/gcc/lib/gcc/11 --disable-nls --enable-checking=release --with-gcc-major-version-only --enable-languages=c,c++,objc,obj-c++,fortran,d --program-suffix=-11 --with-gmp=/usr/local/opt/gmp --with-mpfr=/usr/local/opt/mpfr --with-mpc=/usr/local/opt/libmpc --with-isl=/usr/local/opt/isl --with-zstd=/usr/local/opt/zstd --with-pkgversion='Homebrew GCC 11.2.0_3' --with-bugurl=https://github.com/Homebrew/homebrew-core/issues --enable-libphobos --build=x86_64-apple-darwin21 --with-system-zlib --disable-multilib --with-native-system-header-dir=/usr/include --with-sysroot=/Library/Developer/CommandLineTools/SDKs/MacOSX12.sdk
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 11.2.0 (Homebrew GCC 11.2.0_3)
gcc -dumpversion | cut -f1 -f2 -f3 -d.

Resources